DMA reverts to PIO

Wed, 2007-07-11 08:30 by admin · Forum/category:

The stuttering DVD drive or the lame hard disk

Table of contents

for this article

Quick solution

This is the recommended solution. If you're not interested in the details, but just want to fix this problem as quickly as possible:

  1. Internet Explorer: click, Firefox and other browsers: right-click here.
  2. Internet Explorer: Despite any warnings click on the [Open] or [Execute] buttons as required to execute the file resetdma.vbs.

    Firefox and other browsers: Save the file resetdma.vbs to your hard disk. Double-click on the file in Windows Explorer and allow it to be executed.

    (If you fear that this web site could be malevolent, you could use the manual method instead, which is described below. You can also download, save, and inspect the program with an editor like the Windows Notepad. It is a script text file.)

  3. If the program found any ATA or SATA channel to reset, reboot your computer and test all drives.
  4. If the problem is still not solved, set the offending channel to PIO manually, reboot your computer, set the channel back to DMA, and reboot again.
  5. Please report your results here. Thanks!

Please note that this works only with the Windows drivers. If your device had its own manufacturer's drivers installed, this program cannot fix the problem and will not do anything to them. Instead it will report that no resettable DMA channels were found.

Note also that many CD and DVD drives only use UDMA-2, because their data rate is much lower than that of a hard disk. This is normal and no reason to worry.

If you are interested in the details, read on.

The program tries to reenable DMA in the registry exactly as described below, for all suitable (S)ATA channels. Windows then redetects the DMA status after the next reboot.

If you use the program again after a short while, it may again report that it has reset the channels. This is normal behavior and not a sign of any problem.

General description

This article also applies to Windows 2000. (Peter Frank reported successful application on Windows 2000 with Service Pack 4.)

DMA is an abbreviation for Direct Memory Access, an access method for external devices where the data transfer is not done by the central processor, but by a small special processor called DMA controller. It uses a procedure called cycle stealing, where the central processor memory access cycles are delayed for very short times to intersperse DMA controller memory access cycles. Some newer, faster DMA modes are called UDMA (Ultra DMA).

The alternative, slow and inefficient data transfer mode is called PIO, Programmed Input-Output, where the central processor transfers data byte for byte or word for word. This requires many processor commands for each data word and therefore causes a high and unwanted processor load.

A typical symptom of PIO mode is slow data transfer, accompanied by high processor load, leading, for example, to a choppy video display.

Possible causes for falling back to PIO mode

The most frequent use why a CD or DVD port falls back to PIO mode is a scratched or otherwise unreadable CD or DVD. For example, some newer DVDs, initially from Sony, carry a copy protection scheme that relies on defective sectors. If you try, without using special software, to copy such a DVD (which doesn't work), then this can already trigger the problem.

However, there are a few reasons why a computer may use PIO instead of DMA, particularly when it's the hard disk port that falls back, not a CD/DVD drive port. For example, David Duberman reported in 2005 that some Dell computers have DMA disabled in their BIOS by default for the second hard disk. So it is a good idea to check the BIOS settings first.

2007-05-13 – Jason Paquette confirmed that the BIOS setting in his Dell computer was wrong too and prevented DMA mode. Correcting the BIOS setting immediately enabled the DMA mode.

A not so rare hardware problem is a bad or too long IDE data cable. You need 80-way cables, not the older ones with only 40 wires. With poor cables the device may work, but Windows will probably step down to lower DMA speeds or even to PIO.

A further cause may be waking from standby mode, if one of the involved components does not perform this process correctly.

2007-02-20 – Stefan Welte wrote that on an Elitegroupsystems K7S5A computer all IDE hard disks ran in PIO mode, because automatic device recognition was disabled in the BIOS. (The computer booted from a SCSI disk.) Enabling device recognition solved the problem without any further measures.

2009-06-27 – markvm confirmed again that the BIOS in a Dell computer prevented DMA mode. Please see his comment below. In his case a hard disk was not recognized by the BIOS. After enabling and starting the automatic recognition, everything fell into place nicely, and DMA was automatically enabled by Windows.

2009-11-19 – flemur13013 mentioned again in this comment that setting the disk recognition to "Auto" in the BIOS settings solved his problem of a slow, CPU-gobbling secondary hard disk.

Occasionally a chip set or controller driver is buggy, so check with the manufacturer for updates.

2007-03-01 – Francois Eraud reports one such case in a Sony laptop, regarding an ALI M5229 chip set controller, solved with driver version 4.008.

2008-03-30 – Arran located the elusive drivers for this ALI M5229 controller chip. Please read his comment For those with the ALi M5229 IDE Controller in the comments on one of the next pages.

Other reasons can show up in the event log, so check this first and see if you can find repeated Atapi errors recorded. If so, you likely have a hardware defect. You can use the procedures described on this page, but your computer will probably fall back to PIO mode again and again, until you solve the underlying problem, which may be located inside the device, on the motherboard, or in the IDE data cable and its connectors.

A dramatic example was reported on 2006-12-29 by David Hähningen:

If you (half asleep in the dark and with considerable force) try to put the ATA plug on the hard disk the wrong way around, the gap called "KEYPIN" (pin 20 on the plug) pushes pin 21 of the hard disk socket and bends it aside. (This pin is responsible for DMA requests of the hard disk.)

As the disk can no longer reach the host with its requests, there is a communications problem, and Windows XP switches into PIO mode. A blessing in disguise: You can still save the data, though slower than usual. ;)

Few will succeed in repairing the disk. Just pulling the pin straight may not quite cut it, as the connection to the printed circuit board is probably broken.

2007-02-07 – Carl Kaufmann wrote that he looked for a solution for a computer with an Intel chip set and found the Intel(R) Application Accelerator. As instructed, he first installed the Intel Chip Set Installation Utility, which already solved the problem (as observed in Task Manager). He went on anyway to install the accelerator. After that there was no longer any DMA/PIO choice in the controller options, but everything now works right automatically.

2007-05-15 – John Schumacher confirms:

I thought I was having this problem, but that isn't the case. My BIOS listed Ultra DMA as being disabled on all my drives. I looked for the Advanced Settings tabs for the IDE channels in Device Manager, but the tabs were no longer there. I ran Nero InfoTool, which confusingly listed DMA on for primary and secondary masters, but off for primary and secondary slaves. After doing some more searching, I found out that the Intel Application Accelerator I recently installed is the culprit. Running Intel Application Accelerator confirmed that everything was OK.

The Intel Application Accelerator can also have a quite adverse effect when it is run on an unsuitable processor. If in doubt, uninstall it and retest. (See the comment, Intel Application Accelerator by dkneyle = Ausie Davo.)

The trap

Windows contains a trap in which quite a few computers seem to get caught sooner or later. The trap was described in a Web article whose link no longer works (and also in another one mentioned below):

The crucial paragraphs are:

PIO mode is enabled by default in the following situations:
For repeated DMA errors. Windows XP will turn off DMA mode for a device after encountering certain errors during data transfer operations. If more that six DMA transfer timeouts occur, Windows will turn off DMA and use only PIO mode on that device.

In this case, the user cannot turn on DMA for this device. The only option for the user who wants to enable DMA mode is to uninstall and reinstall the device.

Windows XP downgrades the Ultra DMA transfer mode after receiving more than six CRC errors. Whenever possible, the operating system will step down one UDMA mode at a time (from UDMA mode 4 to UDMA mode 3, and so on).

Of course, drive firmware being quite complex and certainly containing programming defects of its own, it is not all that difficult to produce such errors. In my case a scratched DVD and later also an unreadable (overburned) CD did the trick, got the drive to choke and Windows to disable DMA for good. Later my hard disk hiccupped just once and also went back to PIO for good.

I had been using my laptop for DVD viewing for years, until I inserted a borrowed and heavily scratched DVD. The player and apparently even the DVD drive choked on it, and when I finally got the DVD to play, I found that playing was jerky and processor load was 100%, roughly half of which was system overhead.

This indicated that the drive had reverted from the usual UDMA (Ultra Direct Memory Access) mode 2 to PIO (Programmed Input Output) mode. No amount of resetting or changing the relevant registry parameters from 1 (try DMA) to 2 (force DMA) helped. Stubbornly the drive kept using PIO mode, and Windows even changed these settings back to 0 (use PIO only).

The following text will refer to the secondary IDE port because that is more often affected, but essentially the same also holds for the primary IDE port, to which the main hard disk is connected in most computers.

Before you begin to work on the problem, log on as Administrator or as a user with administrator rights.

Check Your IDE Port Mode

First check what mode your secondary IDE port is currently working in. Go to Device Manager: right-click on My Computer, select Properties, click on the Hardware tag, click on the Device Manager button, click on the plus sign to the left of IDE ATA/ATAPI Controller, double-click on the secondary IDE channel, click on Extended Settings and check whether it is set to DMA when available. Directly underneath that setting is a grey field that shows the actual working mode of your IDE channel. You want the highest possible DMA or Ultra DMA mode there, and you definitely don't want PIO mode.

If the Extended Settings tab is not there, perhaps another driver is used, probably from the manufacturer of the IDE ATAPI controller. You can still perform a simple test. In the Task Manager activate the option View, Show kernel times. Then put a high load on the device, for example by copying a large file, and check whether the kernel times are minimal (red line). If you observe considerable kernel times, roughly around half of the total load, then the device is running in PIO mode, which is bad. The whole purpose of the DMA mode is to relieve the processor (in kernel mode) of this load.

Assuming the Microsoft IDE ATAPI driver, normally you don't have to use the registry editor, because the normal settings are also available through the properties dialog for the IDE port, but if you want to look at it anyway, the parameter for the secondary IDE port can be found through regedit.exe at


It is named Scsi only for historic reasons. Scsi Port 0 is the primary IDE port, to which presumably your hard disk is connected.

After trying various remedies—in vain—I found the abovementioned article and went to work again. I uninstalled the DVD drive in Device Manager and rebooted, but that did not help either.

So I searched for more and better information, then I went on and did the following.

Re-enable DMA using the Registry Editor

This chapter describes the manual way to do what the quick solution at the top of this page does automatically through a script program. If you're not interested in the details, you can back up to the chapter "Quick solution" above and run the script.

My thanks go to my fellow MVP Alexander Grigoriev who taught me this method.

Run REGEDIT. Go to the following key:


It has subkeys like 0000, 0001, 0002, etc. Normally 0001 is the primary IDE channel, 0002 the secondary, but other numbers can occur under certain circumstances. You have to go through these subkeys and check the DriverDesc value until you find the proper IDE channel.

Delete MasterIdDataChecksum or SlaveIdDataChecksum, depending on whether the device in question is attached as master or slave, but it can't actually hurt to delete both. Reboot. The drive DMA capabilities will be redetected.

Note that many CD and DVD drives only use UDMA-2, because their data rate is much lower than that of a hard disk. This is normal and no reason to worry.

2006-01-19 – Horst Schülke wrote that it is sufficient to empty the content of these values. But you can also delete the values entirely. Windows will automatically recreate them anyway, with new content.

Open Device Manager again and check whether the device is now actually using DMA mode. If so, congratulations, you've made it (at least until the next time Windows disables DMA). If not, you may have to change the IDE channel setting from PIO back to the highest available DMA mode and reboot again.

Many thanks to Tomáš Souček, Peter Götz, Alex Vaillant, and Cory Culbertson for piecing together the following information:

There are three keys that work together:


Each bit in these values means a transfer mode that the device may or may not be capable of. Somewhere at MS some of these bits can be looked up.


This is the actual mode the device is running at.


This entry may be the problem child. Peter wrote: "Normally not present in XP, it is created as a reaction to errors. This entry has absolute priority." However, there are doubts whether this is the absolute truth. It is still not entirely clear where this entry comes from. Erasing it or setting it to a DWORD value of 0xFFFFFFFF, rebooting, re-enabling DMA mode, and rebooting again seems to have solved the problem in some cases.


This entry contains the user's setting, manually entered in the advanced device properties. Has the same structure as MasterDeviceTimingMode. This entry appears when the user sets a limited mode manually, such as PIO only.

Another key that seems to create the problem is MasterIdDataChecksum.

All these parameters also exist for the slave drive as SlaveDeviceTimingMode, etc.

More information is needed. If you know anything, please click on Add new comment at the end of this article and write it down.

Alternative Method—Uninstalling the Port

1. Uninstall the secondary IDE port

Attention: Do this only if you use the Microsoft IDE driver that comes with Windows or if you have the driver on hand, because otherwise you may find yourself unable to reinstall the proper driver.

To uninstall the port along with its driver, open Device Manager as follows. Right-click on My Computer, select Properties, click on the Hardware tag, click on the Device Manager button, click on the plus sign to the left of IDE ATA/ATAPI Controller, right-click on Secondary IDE Channel, click on Uninstall. Deactivating is not enough.

Reboot to make the changes active and permanent.

After booting Windows will automatically reinstall the IDE channel and the DVD (or CD) drive. This Plug-n-Play process can take a little while, so give it a minute after the boot process finishes.

2. Check or reactivate DMA

But this may not always be not enough, because unfortunately Windows does not always automatically activate DMA on a DVD or CD drive. You have to check and, if necessary, tell Windows to try to use DMA first. It is possible that Windows XP with Service Pack 2 re-enables DMA automatically on reboot, but I have not tested this yet.

To re-enable DMA, go to Device Manager again. Right-click on My Computer, select Properties, click on the Hardware tag, click on the Device Manager button, click on the plus sign to the left of IDE ATA/ATAPI Controller, double-click on the secondary IDE channel, click on Extended Settings and change the relevant setting from PIO only to DMA when available.

On Windows NT and 2000 you now have to reboot a second time, but Windows XP applies the change instantly. Then you can go to the same place in Device Manager again and check whether the device is now actually using DMA mode. If so, all is well.

Note that many CD and DVD drives only use UDMA-2, because their data rate is much lower than that of a hard disk. This is normal and no reason to worry.

3. Driver is not intended for this platform

If you keep getting the following error message, please read on:

There is a problem installing this hardware.

IDE channel

An error occurred during the installation of the device. Driver is not intended for this platform.

2005-03-30 – Johannes B. wrote: The reason for this error is often that Daemon Tools or Alcohol 120% are installed. In this case the solution described below would not work. But when you uninstall these programs and then restart Windows, it will then install the device drivers without any further problems.

If these programs are not installed, then one possible way out is to rename C:\WINDOWS\system32\drivers\atapi.sys (or a similar path on your computer) to something like atapi.old.

If that's not possible, you can try it from the repair console (boot from the Windows install CD and select the repair console).

If Windows always automatically recreates atapi.sys, you can try renaming it in safe mode or from a command line window or you can try to rename or remove it in the driver cache as well.

Desensitize Your Computer's IDE or SATA Channels

There's a bit more to it. The following article offers a way to reduce the incidence of this problem, although it still doesn't solve it altogether.

IDE ATA and ATAPI Disks Use PIO Mode After Multiple Time-Out or CRC Errors Occur

Do read this article because it contains a useful long-term workaround. But you have to go through the procedure described here to re-enable DMA first.

Assuming you've done that, insert the ResetErrorCountersOnSuccess registry values mentioned in this article into both the primary and the secondary IDE port registry keys as described.

Unfortunately this is only a half solution, because when you enter an unreadable DVD, you will get 6 errors in a row, and the IDE channel will revert to PIO mode, but at least when you pull out the DVD in time and then insert a good one, the error counter will be reset and it will at least be a bit more difficult for Windows to hobble your IDE drive.

A little warning: One user reported that by mistakenly putting the value into the parent key, rather than into one of the 0000, 0001, 0002, etc., subkeys, he was accused by Microsoft's Genuine Advantage check of using a pirated copy of Windows and therefore denied online updates.


Useful info on re-enabling DMA. No more jerky video from primary slave! Thank you

Thank you for a very helpful article. After applying your fix I saw a 10x speed improvement!

Don't mention it!!! After months of trouble-free operation, DVD playback suddenly started to crap out on me, and your site was the only one I could find that remedied this problem. I had been trying to fix it for several weeks when I found it, and boy was I happy. I'm the one who needs to thank *you*!!! Thank you!!! :)

Thank you for the great page on DMA/PIO issues. I had a problem caused by Daemon tools that you covered on your page. Without your work I might never have solved this problem. I intend on donating again after my next paycheck.

You ROCK! Your write-up on Windows setting DMA back to PIO saved me. I was about to take a 12 gauge to my computer. My DVD player wouldn't work for SHIT (stuttering, dropping frames, etc.). I uninstalled my secondary IDE controller, re-booted, & problem solved. THANKS!

Your DMA reverts to PIO page relieved me from horrible sound stututustuttuttering. [...] Hard disk went from PIO mode back to Ultra DMA mode 5 when I uninstalled primary IDE channel in device manager and XP reinstalled it. Thanks.

I love you...
no i don't—but I'm really greatfull that you published this site [...] as I was quite desperate and 24 hours mentally down because my harddisk only managed 2,2 MB/sec (now, thanks to you: 66,2)
best wishes!

Wonderful Dude,
I just want you to know that your posts on how to fix choppy DVD players saved my butt tonight. I love the fact that I can go and search for an answer on the internet, and a good soul such as yourself will have taken the time to post such a clear and excellent series of solutions. [...]

I just wanted to thank you for the information [on this page]. After noticing that my laptop's CD/DVD drive started exhibiting the dreaded "choppy playback" from nowhere (probably caused by trying to read a poorly burned homework assignment handed out by one of my professors a dozen times) I found your advice after a quick search on how to correct the problem. After a few minutes of reading, using the provided script, and rebooting, my drive successfully reverted back to DMA mode from PIO.
Just wanted to give my thanks and have myself counted among the satisfied visitors who were able to fix the issue without any problems. I especially appreciated the down-to-earth explanations for and solution to the playback choppiness. CDs/DVDs play like a dream again, and that really makes my day.

I also wanted to thank you. I almost despaired. For no discernible reason all movies from my DVD drive became jerky. Cleaning the registry and scanning for viruses were also unsuccessful. I was already resigned to the thought of returning the laptop to the manufacturer, because I thought the drive was broken. Luckily there is the Internet and dedicated people like you, who help with good tips.
Many thanks for your work; the article is truly excellent. You're my savior, unthinkable now that I had almost reinstalled the computer.
I hope that many, who have the same problem, find your article.

Thank you very much for your online help to my DMA problem (DMA reverts to PIO). I had been banging my head against the wall for a few weeks before I found your site. The .vbs program worked perfectly to fix my infuriating iTunes & audio distortion problems. For this, I have donated $10 to your site.

Comments, discussion

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Typical symptom: PIO mode (see comment 761). JPG image30.33 KB
dgeorge's picture

WD 2TB Black HDD reverting to PIO mode - RESOLVED

Sun, 2016-12-18 22:25 by dgeorge

I run an XP SP3 PC whose technology was all state-of-the-art c. 2008, built around an ECS G31T-M mainboard with 4GBs of upgraded & overclocked Kingston PC2-6400 memory. There are two IDE controllers (although only one is in use), a Pioneer Blu-Ray internally mounted drive, three 2TB Western Digital WD2003FZEX HDDs internally mounted and a 2TB USB connected external WD drive. It was one of the three internal WD drives that was exhibiting deteriorating S.M.A.R.T. parameters, and I duly replaced it with another WD drive of the same model.

The failing drive was used exclusively to back up four other WD drives in the system none of which contain more than 100 GB of data. The full backup job runs late Sunday night, and had been taking ~2-½ hrs. Immediately after installing the replacement the full backup job required 2 days (about 12 - 13 hours per drive!) It has taken six weeks to eliminate many possible reasons for the drive's poor performance. First, the store replaced the drive with another, but that was just as slow. The backup software is ShadowProtect (excellent product!) by StorageCraft, and using it to back up to one of the other drives it performed quite satisfactorily. The new drive was switched to a different SATA channel with still no speed improvement. It is a bit of a stretch to believe that two units from a reputable manufacturer of the same model and capacity are faulty. As such I was by now proceeding with an abundance of caution. (Not the least of which I didn't want to piss off my local store with a second bogus return request; they have been a terrific resource for the last eight years.) So what do I do?

Throughout this six week period, as a calibration control, I had been measuring the copy time for a 1.25 GB set of files to be moved onto the replacement and the remaining two existing drives. Windows would begin estimating the effort at 35 seconds for all three drives. This would be accurate for the existing two but, the replacement drive, after 30 or so seconds, would begin to fall back to 1 minute, 2 minutes etc., eventually leading to a 12 minute copy period.

After much hunting online the issue of transfer mode was noted, and a quick check of the IDE controllers revealed that, sure 'nuf, the Master on the Primary port had been ratcheted back to PIO while all three other internal drives were in Ultra DMA 5 transfer mode. There are a number of performance monitoring tools available for rotating computer machinery; the one I chose is CrystalDiskMark (CDM) . I had read that Windows fiddles with transfer settings on startup, so a quick re-boot led to the surprising discovery that Device 0 on the Primary controller (P0), new drive, was now back to using UDMA_5 mode.

This encouraging development suggested that a CDM test of the drive was in order. The initial CDM setup was just 50M MB of random data with 32 queues and just one thread for five iterations. CDM reported that the P0 was now producing sequential and random read and write performance equal to the other drives. Following the test, Device Manager continued to report that P0 was using UDMA_5 transfers. The only prior direct evidence I had regarding P0's slow performance were the differential copy speeds between it and the other two WD drives. So, do the obvious: copy the 1 GB file package I mentioned and, while starting off speedily, the copy bogged down into PIO performance which was confirmed by Device Manager (once I have figured out how to use this site I'll post the CDM stats). As a control, the other two disks continue to receive the copy transfers at ~35 seconds per GB. See the attached CDM report for the E drive, DMA transfer rate. P0 took > 12 minutes to copy the file set. Repeat, same sequence: HDD transfer mode on the replacement HDD is UDMA_5 immediately following reboot, and during and after CDM testing (this time using datasets of 100MB & 500MB Q32 / T5, 3 iterations with the new drive on both original channel (as P0) and then as slave on the Secondary channel - S1.) Copy some files to the new HDD and the transfer mode for the new drive degrades to PIO while the other drives remain at UDMA_5. (As a reference for the general performance CDM was measuring sequential reading and writing were in the range 175 - 210 MB/s. Random R/W on the order of 6 - 10 MB/s.)

The matter is still under investigation. I felt I had sufficient evidence to return the suspect drive to my local purveyor, and let them have a go at it. I'll post their findings once I have them.

Update December 17, 2016

The store ran a surface read test using HDD Tune Pro. The performance graph was surprising: reading rates oscillated between 175 - 75 MB/s for every 50 MB read. This periodic oscillation was consistent across the entire surface scan. Clearly, the drive was performing sub-optimally. Since the first drive I had purchased was simply returned and not scanned with HDD Tune Pro, it is unclear whether it too would have exhibited the same behaviour. However, I had recorded it's manufacturing date and country of origin. Both drives were manufactured in Malaysia in August 2016.

The store's support technician suggested that he find a third drive manufactured earlier in the year, and fortunately had one manufactured in April 2016. Before I left with it I asked him to test it so that there would be a baseline for my own testing. The resulting graph showed quite small variation across the surface, with gradually decaying performance as the read heads reach further into the centre of the disks. This gradual fall-off in performance is characteristic of all rotating storage media.

After installing the drive in my own system, I re-started and observed that the transfer mode was UDMA-5, then proceeded to run HDD Tune Pro to verify the drives performance at the store. The results were identical. Encouraged, I proceeded to partition the drive then copy my standard file set onto it. The copy time was 32 seconds, consistent with my other two WD 2 TB drives. A quick check revealed that the transfer mode remained UDMA-5.

I then ran CrystalDiskInfo, obtaining a clean set of SMART parameters. The final test was to run a full system backup. (Recall, this drive was replacing one that had been dedicated solely for holding backup image files.) ShadowProtect backed up the two internal and one external 2TB drives in just over 2-1/2 hours, the same performance experienced with the previous WD backup drive. The drive has now been installed for four days, receiving incremental backups every four hours with no anomalies. I now consider this issue resolved, with the lesson learned to test performance after installing a new HDD before putting it into service.

Unbelievably useful and helpful post

Sun, 2013-11-17 08:30 by KennyL

If I had not 'luckily' come across this thread, I would have wasted a lot of time and effort in re-installing my winxp, or re-imaging my hard drive to some earlier drive image to try get away from the audio stuttering and incapacitating busy hard drive activity. I wasted lots of time using file-explorer and process-explorer etc, and so many things trying to pin down the issue - totally oblivious about the reason behind my issues that the original poster (of these thread) describes. I never would have known. And I think that countless other people out there probably suffered from the same thing without knowing, and would have taken the undesirable route of re-installing the operating system etc - thinking that the registry was corrupted in some way that would be difficult to pinpoint (difficult for regular users of winxp anyway). Thank goodness that this thread exists, as the remedy certainly got rid of my pesky and frustrating problem.

I followed the instructions by going into the registry and finding the relevant registry key (mentioned in this thread), and then I just deleted 'MasterIdDataChecksum' as well as 'SlaveIdDataChecksum' where-ever I could find them. Restarted the computer, and the operating is no longer incapacitated.

It's nasty how innocent unsuspecting users can encounter this kind of issue. Was a real hassle. Thanks very much (to the creator of this thread).

Thanks, but I'm still stumped!

Wed, 2013-09-11 16:04 by Go2Guy

First off, thank you so much for this helpful site, it’s a labor of love! However, I’m still stumped.

I have a retired laptop (purchased in Oct of 2008) that I would like to use for playing music from the hard drive while plugged into my home stereo. Even when there is no other program running, the stuttering is intolerable.

I tried running your script and it didn't work, so I tried following the manual instructions a couple of times. I always got stumped when my computer didn't show the options you describe. I'm hoping you are able to help me dig a little deeper because it's virtually un-usable now, and it seems like such a shame.

It’s a Lenovo SL500 running Windows XP, Service Pack 2. When I run the script, just like you said, I get this message:
“No resettable ATA channels with Windows drivers found. Nothing changed.”

(Would an easy fix be to replace certain drivers with Windows drivers?? Which ones?)

So I tried the manual method by checking the mode of the secondary IDE port; after I click on the plus sign to the left of IDE ATA/ATAPI Controller, I see the following choices

Intel(R) ICH9M-E/M SATA AHCI Controller
Ricoh Memory Stick Controller
Ricoh SD/MMC Host Controller
Ricoh xD-Picture Card Controller


When I double-clicked on these 4 choices, I don’t see “Extended Settings” and also don’t see any mention of DMA. Instead, there are tabs offering General, Driver, Details, and Resources. Within those tabs, there is again no mention of DMA. The driver date is from 2008.

What should I try next? Apparently I have the manufacturer’s drivers rather than the Windows drivers, so I’m unclear which of the other methods (e.g., Registry Editor, uninstalling the Secondary Port) are viable for my situation. I think I can find the Windows discs that came with the computer, if I need to.

Any guidance or suggestions are much appreciated!

Manufacturer's drivers

Thu, 2013-09-12 06:08 by admin

The methods described here work only with the standard Windows drivers. If you have different drivers, then all bets are off.

It is also quite likely that the problem you experience is different from what is described here and has a different cause, but we cannot know, because we do not have information or experience with the manufacturer's drivers.

By the way, the current service pack is 3, not 2. I would install Service Pack 3 first. With a lot of luck it might even solve the problem.


Fri, 2013-09-06 18:11 by Abactor

Thank you very much indeed! For such a terrible user as myself that script really is an excellent solution!

OHDookie's picture

The stuttering DVD drive or the lame hard disk

Mon, 2013-06-03 02:25 by OHDookie


I have this problem for a long time and professional "techies" didn't resolve it.

This GREAT solution enabled me to fix it on the first try - "like butter"! Thank you so much for this simple but powerful solution.

Bravo, bravo maestro!


Mon, 2013-06-03 08:01 by admin

Glad that it helped.

That QUICK SOLUTION Script worked well on a Dell D610

Fri, 2012-08-24 21:44 by DouginSC

Thank you SO VERY MUCH for the time and research and smarts you have put into creating that script! It smoothed out my Dell D610 laptop and now it is usable again (WinXP Pro SP3 w all updates). It was slow and stuttering badly on playing any media including start and shut down sounds. Now it works well again.

One thing, though: I do not have any idea how to run vbs scripts, but I stumbled upon it after I downloaded your file
I found the file in WinExplorer and opened it in notepad to read the text and, after several failed attempts at pasting the text into a run command, I decided to edit the downloaded file name and remove the .txt extension. it is now named simply...
...and when I right-click on that file, windows displays an option to...
Open with Command Prompt
And when I selected that option the script ran as intended and I now have a great working machine once again!

Instructions about how to do that might exist somewhere that I just overlooked. Sorry if that is redundant.

I found this thread in a Bing search and when the fix worked so well I joined this site for the purpose of providing feedback about this experience. I am sure I will learn a lot here in the future.

Thanks to all contributors!


Sat, 2012-08-25 16:49 by admin

The downloaded script file is actually named resetdma.vbs without the .txt extension.

Perhaps the .txt extension got appended on your computer, perhaps by opening and resaving the file in notepad or some other editor.

In any case, thanks for the instructions. They are useful if this happens again to somebody.

Stuttering drives

Tue, 2012-04-10 13:29 by jrplane

I was seing a high level of interrupts using 90%+ of the cpu. The quick fix method of resetting the drive worked.

Take out CDs from drive(s) first

Sun, 2012-02-12 08:11 by ausfly

My computer used to take less than 30 seconds to boot.
One day it started taking 90 seconds for no apparent reason.
I checked everything and then I met this solution.
I ran your program and it reset the drives. Back to 30 second boots.
2 weeks later, I had slow boots back again.
I read this article through and re-ran the program and also took out the old CD that has been in my CD drive for a week or two before the initial slow-down and yippee!!!!
30 second boots with no slow down for at least 24 boots!
Obviously it counted the bad reads on the CD and dropped to PIO.
Thank you for showing me something so simple yet so effective.

Good hint

Sun, 2012-02-12 10:17 by admin

Thanks for this hint. It confirms that a poor CD or DVD or Blu-ray disk can trigger the PIO problem, as mentioned in the main article.

Once we know it, it is easy to understand, but don't ask how many people worldwide have bought new computers earlier than they should have, thinking that the old one was irredeemably broken.

SMS, saved my soul

Thu, 2012-01-26 19:49 by Ernestoch

First things first. I thank you. After several days, I can breath in peace.

Some time ago, I started looking into the Process Explorer resource window a high level of Interrupts. I knew it was HD related. I tried replacing one disc for another. Using an entirely new Windows (XP SP3) installation restored from backup... I reached the MoBo manufacturer... Whatever solution I tried would work for a short period... six errors? six cumulative reading errors? Ha! Alas!
Until last night right after I restored the backup again, just to see the Interrupts rise again. In despair I entered the keywords ... Interrupts.... XP.. but somehow I managed to ask the right question and found the RIGHT answer: this page.

Using computers for 25 years, not only from the outside but also from the inside (selling, supporting, teaching) I was astounded for not being able to identify the reason. I ran the script, almost sure that the next step would be to get a new MoBo. But no, this time it feels different, and I know where to look and how to fix it. I still have to connect the other HD to the PC, but I feel confident now to find a permanent solution. The KB solution will be implemented too, but I have to see if the HD is damaged or something else caused the PIO mode to appear, cable, power, I'll find out.

Thanks a lot.


boster's picture

Help for Win7?

Fri, 2011-12-23 01:12 by boster

I'm on Windows 7.

The good news is that I LOVE learning about this, and the DMA-to-PIO downgrade explanation very much explains what I'm experiencing on a secondary/slave hard drive. The device manager doesn't show what mode the device is in, but Task Manager, with Kernal times turned on, does show about 50% of the CPU utilization.

The bad news is that I can't fix it.

1 -- Device Manager does not show the current state, nor allow me to enable DMA. Under "IDE ATA/ATAPI Controllers" I have "ATA Channel 0" which appears to be connected to my CD/DVD drive; on the Advanced Settings tab it lists one device, called "ATAPI Cdrom" and has an "Enable DMA" checkbox, which is checked.

I also have "ATA Channel 1" which says it supports 2 devices, but does not list any. This, like Channel 0, is Microsoft standard.

Then I have "Standard Dual Channel PCI IDE Controller". This is also a Microsoft driver, and lists no devices.

I tried unchecking and then checking "DMA" on the first channel, but expected no change since it appears to be for my CD/DVD drive. And I got no change.

2 -- I checked into the registry. Went to the {4D36E96A-E325-11CE-BFC1-08002BE10318} key, found the 0000, 0001 and 0002 subkeys as suggested, but couldn't find MasterIdDataChecksum or SlaveIdDataChecksum.

3 -- I tried uninstalling "ATA Channel 1". Rebooted. Windows 7 did indeed reinstall it. But no change. Still sporadic periods of slow-to-a-crawl on that second hard drive.

4 -- While I didn't see this recommended, I also tried uninstalling the appropriate disk device under "Disk Drives" in Device Manager. After reboot, Windows 7 reinstalled it, and there was no improvement.

5 -- I did also run the VBS script, but it reported nothing to fix.

So I appear to have the problem that Windows 7 has dropped to PIO (or sometimes drops to PIO--sometimes it operates very efficiently), but I don't know how to fix it.

Any help?


Reply to Boster Re audio interference every 2 mins on Dell Lapto

Wed, 2012-06-20 17:26 by Janglyj

Hiya Boster.

Fix for Dell laptops running windows 7

I have had an audio interference problem for months on my Dell Inspiron laptop running windows 7. It occured every 2 minutes whether playing disks, music/tv/video etc online from hard drive or live streaming (I have a problem with the laptop refusing to back up or install auto updates fully but that's another story). After reading through this forum I discovered screens I didn't know existed and had a fiddle around. The solution I found has fixed it for me 100%. Its a joy after so many frustrating months. I have posted what I did for you and fingers crossed it helps and you can regain your sanity. It seems so simple but believe me I tried everything for the last five months and had no joy until now, so here goes.
1, Click the start button from the desktop
2. Control panel,
3. Hardware and Sound,
4. Devices and printers - Device Manager
5.Find ide ata/atapi controllers+intel(r)ich9m-e/m sata ahci controller on the list. Double click on this.
6. Choose the 'DRIVER' tab.
7. Click the 'ROLL BACK DRIVER' button

Worked for me. Best of Luck.
If anyone on here can advise how you set a roll back date in Windows 7 that may help. Windows 7 really does not provide many options for us to fix things ourselves anymore. Having a PC that does all the thinking for you(in theory) is very frustrating.

Kind regards


Fri, 2011-10-21 20:55 by wayne

Not only did it work, but the difference was like night & day.

NERO now writes a DVD move in 8 min (at 8x) instead of 30-60.

My photo browser starts so fast that it is scary (got to get better pics LOL)

Works like a charm

Tue, 2011-10-04 15:42 by chinhodado

I sign in just to say thank you. You are my savior!


Fri, 2011-09-30 22:10 by dougd2

Your described fix was the problem.
This solved days of 'now what'
I have passed your fix on to others as well as your link.
many thanks

Thank you!

Sat, 2011-09-24 07:03 by sigil

After opening a DVD with the InterVideo program on my Toshiba laptop (XP Pro) DVDs were choppy when played back, both in that program and in Windows Media. I couldn't get my IDE controllers to accept DMA, but your vbs file did the job, and now DVDs play perfectly again.



Sun, 2011-09-04 06:29 by Snowsharkeus

So, I spent the last several hours trying to figure out why the music I was streaming started getting super choppy, distorted, and just plain un-enjoyable!!

I had tried everything and the problem was persistent whether I was streaming Rhapsody or Pandora, then I also noticed that even the Windows start-up sound was distorting...really weird. I tried both the onboard sound card AND my Rocketfish PCI sound card. Again, same results!!

Somehow one of my numerous Google searches let me to your solution. Wasn't sure it would fix my problem, but voila, it's all good now.

In fact to test it out I fired up Rhapsody and Pandora at the same time and streamed songs through them, then I added CNN with a streaming news piece, and finally a YouTube video...all four pieces of media streaming simultaneously without any audio OR VIDEO problems.

Again, thank you!!


DMA to PIO reset

Fri, 2011-05-13 09:28 by holmsn

What an incredible resource this site is !
After dismally considering a re-install of a backup image from Windows Home Server ( better than nothing I suppose ) when the whole machine had completely slowed down , with the stuttery start up jingle, incredibly extended boot times and complete failures of further backups to the server I happened across this marvellous site by Googling.
Many,many thanks.


PS I have passed the word to a few Windows savvy friends, as I am sure this is very much a "hidden" Windows problem

rrhobbs's picture

PIO Mode fix

Mon, 2011-05-09 13:44 by rrhobbs

This was GREAT - thank you!

A Thousand Thank-You's!!!!!!!!

Sun, 2011-04-10 06:22 by DeltaSierra

I've experienced this problem repeatedly over the years with my home-built system, never being able to find out what the cause was, before deciding to simply start over again and re-install Win XP, but after a few months it would happen again and I'd bang my head on my desk in frustration. I can't thank you enough for this solution - it was so easy and it worked!!! I thank you (and my desk thanks you!)

Thank you!

Thu, 2011-03-31 17:33 by darkhorse

I registered just to say a big thank you! I've been building and troubleshooting computers for myself family and friends for the past 15 years, and have never come across this problem before. My sister complained that the DVD player in her laptop had stopped working properly and that when she tried to watch films it was impossible. Until I arrived on this website I had no idea that WinXP was automatically reducing the capability of her DVD player because she had been playing scratched disks. Anyway problem is now solved and DVDs running smoothly! Thanks again!

DieHard the Hunter's picture

I am clearly dealing with an expert!

Thu, 2011-01-27 02:29 by DieHard the Hunter

Mate, I have gone thru some considerable effort to join this forum and leave this comment, for the sole purpose of thanking you for your excellent solution to this persistent problem, and for the completeness and correctness of the solution you have provided me. It was certainly worth the effort, for both of us!

It is truly refreshing to be helped by somebody who clearly knows what he is talking about. The solution provided worked instantly, and completely. As an added (and unexpected) bonus, I now understand the nature of the problem, why it happened, and why the solution provided fixed it.

You were 100% right: I did try to play a scratched DVD, and my machine responded precisely as you described. This had me puzzled, until you explained it for me. Now it makes perfect sense.

So, thankyou sir! I am clearly dealing with an expert, and I'm very grateful for the solution you have provided. If you ever need a testimonial, let me know -- I would be delighted to provide one.



Thu, 2011-01-27 15:58 by admin

Thanks for the offer of a testimonial. This here should already do fine.

Yes, it's good to have at least one of the many errors explained in detail and the problem solved as well.

In fact, I cannot take all of the credit. The error was thoroughly analyzed by at last two other people. I can only take credit for bringing the people and the information together here and publishing the results in a form that is, I hope, understandable. I did write the quick solution program though.

Your one-click link fixed my slow (PIO not DMA) Dell PC!

Sun, 2011-01-02 14:21 by Roy22

Many thanks! Your one-click link did the job!

For the benefit of users who like me may stumble into this vital webpage whilst seeking a cure for their oddly slow PC, here's my story.

About a week ago, my Dell Dimension 5100 started going surprisingly slow. Sure, you expect a 5 year old PC to be a little sluggish, but this was sudden and very noticeable. File transfers between disks took far longer than normal. My weekly Acronis True Image backup had to be aborted, having not even finished the initial backup overnight, normally done in an hour or less. The odd thing was however, no errors were showing up at all. I ran my virus scanner which found nothing bad lurking. Task Manager confirmed the processor was mostly just idling with system idle processes. I tried Seagate's Seatools (I have two identical sata Barracuda 1.5Tb drives, ST31500341AS, one as system the other as data) and whilst the short drive self-test reported no problems, the long version took so long I had to abort it. I should have (but didn't) check the second data drive at this point.

Still wondering about some weird HDD problem, I ran the most thorough Windows drive check (chkdsk c:/x/f/r) which cuts in after the next reboot. It always takes an age, but this time took most of 24 hours to complete. Frustratingly, the windows event viewer confirmed it fixed only a few minor problems, and made no noticeable improvement.

Next I ran HD Tune. Wow! The second (data) drive was as it always has been, averaging 85Mb/sec. But the system drive was under 3Mb/sec!! Googling this led me to your page, and checking the device manager confirmed the first IDE interface was now running in PIO mode despite being marked 'DMA if available'. And windows won't switch it back again?!

Running your tool plus a reboot fixed things immediately. HD Tune now gives both drives as 95 & 94Mb/sec respectively, an improvement on both! I'm not sure why device manager now says the first (system) drive is Ultra DMA mode 2, whlst the second data drive is mode 5, but it seems to have made little practical difference.

I am indebted to whoever found this problem and made available such an easy fix. I'm appalled that Windows can downgrade the communication speed of a drive without a) making an announcement to warn the user and b) without offering any switch-back option. But thanks to this brill website!

Thank you so much for this tool

Mon, 2010-12-27 20:28 by Merel

I have been trying almost two years to fix a sound problem in my Windows based computer. I have been searching with Google and found numerous reports where sound was produced in all sorts of manners ... except in the normal way.
This can be true for any machine running on Windows, regardless the hardware used. (It is called the TRAP here)

Only one common point : Windows !

My PC was running without any sound problem with Linux.
However the issue (PIO / DMA ) is almost totally unknown by great majority of Windows users and therefore never mentioned..

The QUICK SOLUTION is the best tool I ever used ! And indeed it is QUICK !

Besides the fact that the sound problem is gone (at last!) It changed my slow old PC back into a racing machine, in just a few seconds

Thank you again.

vradul's picture

Thank you, Hans

Sun, 2010-11-21 15:35 by vradul

I had a motherboard burn out a few weeks ago due to a power outage and power coming back while I was out and had left this machine running. As I have years of client data stored in Outlook folders, and projects in process, and although I image the drive every night to an external USB drive, I didn't want to take the time to build a new system and transfer everything, as I needed to get back to work the same day, so I replaced the motherboard with an ASUS P5PE-VM that would boot this XP-SP3 system.

I've had the odd disk error appearing in event logs since, and after a couple of weeks the new system s-l-o-w-e-d down drastically - the Secondary IDE Channel had reverted to PIO - and I started experiencing bad sound problems - static, choppiness, etc. - I have music playing nearly continuously, and get all my news online - don't watch tv at all - so the sound problems on top of the slowness of the machine were very frustrating.

My system is on an IDE drive although I have SATA controllers as well.

Your script worked perfectly - and reset all channels to DMA if available and used channels to Ultra DMA 5. This morning is the first day in 2 weeks I have no sound problems, and a machine running much faster.

Nice work, Hans! I'll distribute the link to this page widely.

Good to hear

Sun, 2010-11-21 15:52 by admin

Is the main hard disk connected to the secondary IDE port? Normally it is connected to the master connector (at the end of the data cable) of the primary IDE port and the DVD drive is connected to the secondary port.

Not that it matters much, but it is not always good to have both the hard disk and the DVD drive connected to the same IDE port.

vradul's picture

DVD is on a separate port

Sun, 2010-11-21 18:34 by vradul

I was a little surprised that the main drive turned out to be on the Secondary IDE Channel, as it is connected it to the only IDE connector I can see. My local shop put it together for me. Maybe the SATA is the Primary channel?

BTW, one other indicator of how important it is to have channels set properly is that my nightly backup drive imaging takes about 2 1/2 hours with the channel set to PIO... but less than 20 minutes with DMA.


Sun, 2010-11-21 21:58 by admin

The main point is that hard disk and DVD are not connected to the same port, i.e. not connected via the same data cable. Even that works, but the slower device can slow down the faster one.

First of all, good advice,

Thu, 2010-10-21 03:19 by angeloslev

First of all, good advice, helped me identify the problem (had it in other PC some years ago, never found out what it was).

However, in my case, it's a little different, so the hotfix (or manual registry change) won't fix it (isn't even needed).

Let me take it from the start:
I have a new WD 500GB SATA2 HDD and 2 IDE DVD-RWs (only IDEs on the system). I was told that SATA and IDE might not work out and indeed it took some tweaks, but done it eventually).
Everything works perfect all the time, disk goes fast (reported almost 100MB/sec with some HDD check utilities) and READING from both DVD-RWs also works fine.
Also, when I first installed windows (Win XP SP3) on the machine writing DVDs also worked fine (with NERO 8 and other programs).
In the meantime I installed some more programs and here comes the problem:
Whenever I try to write a CD/DVD with Nero or any other program, after a while the PC slows down dramaticaly, the writing process also slows down (underruns all the time) and HDD speed is reported as 0.7MB/s (!) from said utilities.
I strongly suspect the HDD reverts to PIO, as it is still slow if I end the DVD-R process and try to resume regular work on the PC.
However, after a restart, all is back to normal (until I try to burn a DVD again).

Now, I suspect that all this is due to the installation of some program named "Aspi rip" which prompted me to install ASPI drivers for Win XP (which I did, silly me). I mainly did that so that Audio Catalyst 2.1 (I liked that a lot) would work, and it did.

My problem now is that although I have an idea about which files that program installs (probably ASPI32.SYS, WINASPI.DLL, WOWPOST.EXE and WNASPI32.DLL), I am afraid to delete them, as they may be needed anyway.
I would like to replace them with newer versions, but not sure where they are (those I have now are 2001ish dated, whereas I found a couple of them -in Nero's folder for example- 2007ish dated).
Mind you, reading windows support pages, I did see something mentioned about that RCR errors "relaxing" change with ASPI mentioned, so I guess that must be the reason.

Any help or suggestion would be greatly appreciated, before I start changing stuff and doing more harm :)

EDIT: From some more looking around, I have a feeling that this problem cannot occur on SATA HDDs, as they DON'T revert to PIO mode. It could be that the DVDs do it when I try to burn a DVD (using the outdated aspi drivers?), but that doesn't sound right, since, as I said, even when I stop the burning session and stop all DVD action, the PC still runs very slowly (and HDD speed is reported as very slow). Only a restart fixes the problem.

UPDATE: I updated those aspi files, from Adaptec..Nothing.
I then updated windows DVDs and also IDE controller drivers... Nothing.
I then uninstalled that ASPI RIP program and also plain deleted those files, including Aspi.sys and wnaspi.dll...Nothing
Still Nero (and 2 other programs I tried) start trying to write the DVD and after a while (5-40%) the pc almost dies with HDD reaching 0.5MB/sec speed).
As long as I don't try to write a DVD the PC works fine.

Different problem

Thu, 2010-10-21 14:32 by admin

Your problem may be related, but is essentially a different problem, not caused by the mechanism described in the main article at the top. Since few people will have similar setups, including ASPI drivers, you may be on your own.

But let's see, perhaps somebody passes by here and knows something.

Have you considered throwing out the IDE devices and replacing them with SATA drives? If you already have SATA …

I guess it can be different,

Thu, 2010-10-21 19:37 by angeloslev

I guess it can be different, yes.
I suspect it's similar, as in windows making the HDD go to PIO mode, but unfortunately I can't see if that's true from Device Manager.
What bugs me is that a. It all works fine till I try to burn a DVD and (mainly) b. it was all working fine till a couple of days ago, i.e. it CAN work. It's just that something I installed did the damage.
As for replacing I have thought of it tbh, but I got no money to do it atm (and I can't even be sure it would fix the problem, anyway).

Uninstall ASPI drivers?

Thu, 2010-10-21 20:19 by admin

Have you thought of uninstalling the ASPI drivers?

Another thought is to do a repair installation. Chances of that solving the problem are more on the slim side, but it may still be worth a try, since you would not really lose anything (unless things go wrong, which they always can in such operations).

I did uninstall the ASPI

Thu, 2010-10-21 22:58 by angeloslev

I did uninstall the ASPI drivers. Actually, I first tried updating them, then uninstalled them completely (even made sure the files were deleted and no ASPI was reported by ASPI-check etc). No luck, though.
As for the repair install, yeah, I've thought of that, but tbh, I also believe it won't fix anything (it usually fixes stuff when there is something missing, not something added, as seems to be the case here) and I'm reluctant to do it with so little chance of fixing it, specially since it can cause other long-term problems (repair install has always been the first step towards clean install in my experience, and I just made a clean install a week ago). Still, i may try it if nothting else works.

I'm trying to find which program changed the situtation (as it was fine before), but I did install quite a few of them (new HDD), so it's not easy.

Good luck

Fri, 2010-10-22 07:18 by admin

I know this is a difficult situation. Wish I had some better recommendations, but I can't think of any.

Generally Windows with the needed range of third-party software resembles a house of cards. The operating system is everything but stable and not resistant to side effects from other software. For the most part it doesn't tell you what's actually happening in the computer either.

Many people have resorted to regularly installing everything from scratch, which solves many problems but incurs a huge cost in terms of wasted time. To reinstall my main computer would take me at least a week. I've never done this. My system has been upgraded at least since Windows 3.0 (if not 2.1), but I admit that the wasted time to fix problems was still too high.

Microsoft has now failed to continue the upgrade path. There is no way to upgrade from Windows XP 32 bit to Windows 7 64 bit, so now I may have to reinstall from scratch, because of Microsoft's failure. But I'm digressing.

Yeah, installing from scratch

Fri, 2010-10-22 21:05 by angeloslev

Yeah, installing from scratch is a pain (I did it twice in the last 2 weeks). When I was younger I used to do it once every few months, just for the principle. I'm amazed you haven't done it since WIN 3.0 (I started with win95 anyway :P). Still, it's doable, but it feels much better if at least you have had some months of good operation before you have to do it again.

Anyway, I found a semi-solution to the problem. Actually not sure what it was the made it work, since I did a hundred updates and upgrades and drivers installs and program uninstalls etc (including the hotfix that Microsoft suggest -the registry edit to make it 6 consecutive errors, instead of 6 cumulative ones- and your solution here).

In any case, DVD-burning now works almost fine. I.e. It starts perfect, as it was when I first installed Windows, and at about the time that before it used to almost totally kill the PC (revert to PIO?), which is anything between 10-40% completion, now it slows down some, updates the completion time by 1-2 minutes and I get buffer underruns, but only 3-4 of them (instead of a 100 or more before). It then finishes fine.
It's not as good as it was at the start, but it's much better than a few days ago, when I wrote this, so I'll consider it "fixed". Still, I don't know what caused that and I'm sure there must be a better solution. Maybe now it just reverts to a slower DMA (from default 6), or something, every 6 consecutive errors and then again after 6 more etc, with no time to go into PIO before the DVD-burning ends.

Unfortunately there's no way to see what mode the SATA drive is running at, from inside windows and, specially, there's no way I can find which program made what change. Maybe next clean install I do, I will monitor everything and find out, as I'm sure when I first installed Windows, a week ago, it was working perfect.

Good luck with your clean install :)

Device Manager

Sat, 2010-10-23 09:51 by admin

In Windows XP I can see the SATA mode in Device Manager under "IDE ATA/ATAPI Controller". To my knowledge, SATA does not have anything like PIO mode. It could only step down to a lower speed.

But problems with DVD burning are usually not caused by the hard disk, but by the burner or its controller and data channel.

If you get a chance to swap the DVD burner for another one, even only temporarily for a test, you could try that. Perhaps there is something wrong with the burner after all.

I guess if it cannot swap to

Sat, 2010-10-23 16:44 by angeloslev

I guess if it cannot swap to PIO, but it CAN step down, that's what it does, for some reason.
I have tried 3 different burners, all with the same result (all IDE, though).
Don't forget, that as I said, when it happens the HDD goes terribly slow, even after I stop the burning and also that a HDD testing utility I have reports the HDD speed as +-0.5MB/sec, whereas it tests it as 80-100MB/sec in normal mode...

Really strange

Sat, 2010-10-23 19:26 by admin

If you wanted to get to the bottom of it, you'd have to swap components until the defect disappears. It could be the controller, in which case only swapping the whole motherboard would help.

It could be the hard disk, one of the data cables, etc. Or it could be some kind of software problem, in which case swapping hardware might not help at all.

Using IE 9 beta, can't seem to download the file

Mon, 2010-10-18 13:04 by newly_53

I am kinda new to this, I am using IE 9 beta and cannot seem to download the fix, I am a little leary about using the registry editor, can you advise me how to work around the IE 9 beta to download the file, when I click at the spot I get the script written on a page, no executable file. I am also using windows 7 and suspect that one of the video editors I have downloaded may have changed the file to PIO. Any help you can offer would be greatly appreciated and I would like to thankyou in advance


Follow the Firefox advice

Mon, 2010-10-18 16:49 by admin

In the explanation there is a distinction between Internet Explorer and Firefox, and it seems that your beta version behaves more like Firefox.

Even though I'm very experienced, I do not use beta versions, because in my experience they are too full of errors to even try to test them. If you are not a very experienced computer user and know pretty exactly what you're doing, I think you should certainly not take part in beta tests. Beta software is generally not supported here. If you use it, you're on your own.

Thanks for the easy solution!

Fri, 2010-10-15 15:48 by TheMauriceV

I actually registered just for the purpose of sending you this thank you note, since you saved me so much time. I was about to format and reinstall Windows on my little Acer Aspire One when I stumbled across this elegant solution to an annoyingly persistent problem.

So thanks again!

Saved my hard drive. Thank you so much!!

Wed, 2010-10-13 01:43 by pankoz999

No clean windows install no nothing. Just run the script file and done.
I must say right now this article has been the most helpful in my entire pc-solving-problems knowledge.
I even though that my motherboard had failed or that i had a hardware failure. The lag on almost everything i did on my pc was soo frustrating cause i couldn't imagine a reasonable explanation.
I'm really thinking now dumping windows. I've been through a hell for 2 months cause of this.
Again i'm really so very much thankful for this, i registered just to write this and i'll read from now on the hole content of the site!! Keep doing that great job!!

Great Success!

Tue, 2010-10-05 16:37 by TheEfficientBaxter

Many thanks to the author- running the script cleared the problem up immediately. I had the usual symptoms- crackly, rippling audio, slow system, and high processor usage due to interrupts. I was worried that I'd have to do a fresh XP install... Not so! Thanks again.


Sat, 2010-09-25 09:46 by nyser1

I've been having audio problems with my Acer Aspire One netbook (XP) almost from day one. Playing videos online was usually the trigger for the sound to begin stuttering and then it would affect all the sound on my computer - including the startup and shut down tones. I tried a lot of things, but the problem would seem to go away as mysteriously as it began, only to strike again weeks later. In addition, the computer's startup speed became ridiculously long.

After researching feedback on your fix and with some amount of trepidation ("Dear God, please don't let this be malware!") I tried your quick fix and it worked! As promised, in seconds and after a restart, everything seems to be working fine. I restarted again to prove it wasn't my imagination, and it wasn't: the startup speed has also dramatically increased! I'm crossing my fingers that everything stays this way. Thanks!

Help with regedit

Wed, 2010-07-28 15:54 by Lehusky

Hi i am a mac owner but i'd like to help my girlfriend with a sound stuttering problem
on her Aspire one laptop. Google search got me here but i would need a really basic, step-by-step explanation on how i run a script in regedit. I don't what to do with the file, where exactly in regedit i should copy this script and even if i should copy the entire text of the script or just a portion of really basic tutorial please, did not find answers on google so i try here, thanks!

DMA reverting back to PIO

Fri, 2010-07-16 21:58 by circawdm

Thank you so much for the quick fix. It all rolled by fast on my screen while fixing things and I saw alot of things corrected in the end. The MAIN thing is I am in DMA 5 IDE now on primary and secondary, and it seems to be staying there after MANY reboots and running my usual programs. I think an antivirus or other program I no longer have messed things up. I will hope and pray it stays fixed, as I am below low on money to pay someone in real life to diagnose and fix things. With a new, very fast, top of the line parts computer (gift) I hope this took care of things. All the hardware checks I ran were normal and not defective.

I have the newest, fastest WD hard drive for my C drive also, but the rest of it is too technical for me to understand very well. I am just glad the quick script worked and hope it stays fixed!

Thanks VERY much to the person who created that script to run!


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