PIO/DMA mode problems in Windows XP


Recommended Posts

My Samsung DVD player reverted to PIO mode on the secondary IDE channel though when installed it was set to Ultra DMA mode 2.

I was unable to restore it back to DMA mode. It seems that Windows XP will downgrade a device after six or more CRC errors.

After checking various solutions, some people suggested editing the registry and Microsoft (see www.microsoft.com/hwdev/tech/storage/IDE-DMA.asp) recommending unistalling the device then reinstalling the device (I tried this and it did not work). I found the easiest solution was to uninstall the secondary IDE channel itself, then let Windows check for hardware changes. It will detect the secondary IDE channel and restore devices to DMA mode. All without having to reset the computer.

Hope this is of some help to users.

It seems that this is a common problem with Windows XP.:)

Link to comment
https://www.neowin.net/forum/topic/19007-piodma-mode-problems-in-windows-xp/
Share on other sites

Hmm...Thanks for the tip.

Perhaps this has something to do with my CD-RW freezing my computer (e.g no mouse movement, no system activity, complete freeze) when I put a blank cd in and it's accessed by windows (which is every time, becuase windows is trying to read the CD and see it's format... :p )

I have a Kenwood 72x cdrom drive and I did a nero cd speed test on it yesterday and it never broke a read speed of 16x. Also, I tested my cdrw 32x read and it broke 32x. I have both of these on the same channel. My hdd wont work unless this is the setup. The cdrw is on ide2 master and the cdrom on slave. When XP installed, it set the Kenwood to PIO mode, and I have changed it to DMA and it has stayed there. Now, if i change it back, will it perform better or should I just leave it where it is??

Posted in Hardware help section. I didnt get any answers here.

This happens to my HDD too, don't know why, just can't set it back. It's not possible to uninstall the main HDD while running XP, so the solution there is not valid for me. I've try to change the setting from ENABLE DMA to PIO, then switch back, but it doesn't work. My BIOS & mother board of course supports DMA and it works fine in WIN ME.

Anybody has a suggestion?

  • 1 year later...

I know that this is hardcore thread resurrecting :rofl:, but I would like to thank Marko & the Neowin Search Engine for solving this exact problem I had with my optical drives today :yes:

Thanks again Marko & Neowin Search Engine (Y) :happy:

Radish?

heh, I had the problem with my DVD drive not being in DMA mode, but I had to switch my dvd drive from master to slave on the secondary IDE cable in order for it to become DMA. Heh, I didn't know that the search engine even searched back a year and then some :)

I have a Kenwood 72x cdrom drive and I did a nero cd speed test on it yesterday and it never broke a read speed of 16x. Also, I tested my cdrw 32x read and it broke 32x. I have both of these on the same channel. My hdd wont work unless this is the setup. The cdrw is on ide2 master and the cdrom on slave. When XP installed, it set the Kenwood to PIO mode, and I have changed it to DMA and it has stayed there. Now, if i change it back, will it perform better or should I just leave it where it is??

Tried to find your post in hardware help, I remember reading about the kenwood 72x's they used a split lazer to achieve the high velocities that they ran, and there is no firmware update to make that available in XP.

Thats why your 72x only goes 16x

Kenwoods were also notoriously unstable, the ones who loved them were the ones that it worked for.

  • 1 year later...

Windows XP has an obnoxious relic from the old days. When a hard drive started going bad, a cyclic redundancy check error was generated and tracked by the registry. After several errors, the hard drive was noted as failing and Windows would drop to lower and lower levels of DMA until Programmed Input Output mode was the only thing left to run the aging and/or failing hard drive. Now the idjits at Microsoft have continued this practice with devices that have removeable media. Several scratched cds or dvds later, a couple of buffer overruns or whatever, and your CD/DVD runs slowly or sometimes not at all.

Here is the fix. Run regedit, navigate to the following key.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E96A-E325-11CE-BFC1-08002BE10318}\000X

Where 000X corresponds to the various drives on your IDE bus. Likely, 0000 will be your primary hard drive,but who knows (or cares). IN each 000X key, look for "MasterIdDataCheckSum" or "SlaveIdDataCheckSum". If you see either one or both of these right-click on them and delete them. A dialog will pop up asking you to confirm the Deleteion. Click OK. Do this for each drive 000X. Restart when done. Problem solved

Another massive thread ressurection but it's some good info that would have proved useful to me about 6 months ago.

To clarify a bit more on the 000x keys.

0000 is the IDE master controller (nothing to tweak here)

0001 is the primary IDE channel

0002 is the secondary IDE channel

Nice tweak. I had bad DVD with CRC errors on it and repeatedly tried it in both of my optical drives. Now for a bit of preemptive registry editing.

yep you did the right thing. just unistall the idechannel, let windows re-recognize it aftera reboot. easiest and simpliest way to handle this problem.

585806377[/snapback]

Unfortunatley that method doesn't allways work. I had a hell of time fixing that issue the last time it happened to me. Removing the IDE channels caused more problems. For some reason if I do that, windows endlessly detects new hardware (the ide channels) and if I tried to let windows install the drivers it would fail with some "Drivers are not intended" error. The only way I could fix it was to install the VIA IDE miniport drivers, change modes and then remove them. I have an older abit mobo with a via 686b southbridge and amd 760 northbridge. For some reason I've only ever had trouble removing and letting windows re-detect with that combo. Newer hardware I've worked with lets me remove the channel without problems. The regedit is quick and painless.

cheers dude! this has been niggling me for a few weeks after installing a new dvdrw.

both back to UDMA again (Y)

my asus dvdrom stopping running on UDMA5 mode and reverted to pio.

the removal and installation of the controllers didnt work in this case and deleting the reg entries was the only option.

This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Posts

    • Quantum Error Correction Validated in Nature: Microsoft and Quantinuum Log 800-Fold Improvement Two years after the original press-release announcement, independently peer-reviewed results published in Nature on June 10, 2026, have confirmed that Microsoft and Quantinuum achieved an 800-fold reduction in quantum error rates on real trapped-ion hardware — the largest gap between physical and logical error rates ever independently validated.    What Quantum Error Correction Actually Does — and Why Breaking Even Is Hard https://www.techtimes.com/articles/318329/20260613/quantum-error-correction-validated-nature-microsoft-quantinuum-log-800-fold-improvement.htm   Quantum Computing Wiring Bottleneck Cracked by HKU Silicon Carbide Chip at Qubit Temperature Engineers at the University of Hong Kong have built the first cryogenic control chip that operates at the same temperature as superconducting qubits — 10 millikelvin, or just one-hundredth of a degree above absolute zero — without generating the heat that has forced every competing approach to park its electronics hundreds of meters of cable away. https://www.techtimes.com/articles/318325/20260613/quantum-computing-wiring-bottleneck-cracked-hku-silicon-carbide-chip-qubit-temperature.htm  
    • RevPDF 4.5.0 by Razvan Serea RevPDF is a free, fully offline PDF editor for Windows, macOS, and Linux that lets you edit text and images directly inside PDF files — no internet connection, no account, and no cloud uploads required. Unlike bloated alternatives that demand subscriptions and constant connectivity, RevPDF fits in under 60MB on desktop while delivering a complete editing toolkit: annotate, redact, sign, compress, split, merge, convert, and reorganize pages, all processed locally on your device. Smart font matching ensures edited text blends seamlessly with the original, and multi-language support includes RTL scripts such as Arabic and Hebrew. Where most PDF editors force you to choose between features and simplicity, RevPDF manages both. You can build interactive forms from scratch with text fields, checkboxes, and dropdowns, permanently redact sensitive data before sharing, draw freehand on contracts and diagrams, and add custom watermarks — all without a single file leaving your machine. Edit Text and Images Directly Inside PDFs RevPDF supports true inline PDF editing — not just annotation layers on top of a document, but actual modification of existing text and images within the file. A smart font-matching engine identifies the font used in the original document and applies it automatically when you make edits, so changes blend naturally with the surrounding content. You can reposition elements, resize images, and update text across single pages or entire documents. RevPDF 4.5.0 release notes: This is one of the biggest updates to RevPDF yet. A lot of things people have been asking for are finally here. New Features Auto Redaction Permanently redact sensitive text and areas from your PDFs before sharing. Clean, irreversible, and fully offline. Comments, Links & Bookmarks Add comments for review, insert clickable links, and create bookmarks to jump around long documents without scrolling forever. Find & Replace Search across the whole document and replace text in one go. Long overdue. Split Pages Vertically or Horizontally Split any page down the middle, vertically or horizontally. Perfect for scanned books or double-page spreads. New Drawing Tools More tools for freehand drawing and markup, better for annotations, sketches, and detailed notes. Continuous Scrolling in Editor The editor now scrolls continuously through pages instead of jumping between them. Working through long documents is a lot smoother now. PDF Metadata Editor View and edit the metadata stored inside your PDFs, including title, author, subject, and keywords. Better Font Matching Text edits now blend in more naturally by doing a better job of matching the original font. Tabbed PDF Viewer Open multiple PDFs at once in tabs and switch between them without going back to the home screen. Add Links Insert hyperlinks anywhere in your PDF, to external URLs or to other pages within the document. Share & Print Shortcuts Share or print directly from the editing screen, home screen, and viewer. No extra steps. Minor Updates Paste images directly from clipboard into your PDF New image editing tools for more control over images inside documents Bug Fixes Fixed file saving issues on Windows and Linux Everything still works fully offline. No login, no cloud, no account. Your files stay on your device. Download: RevPDF 4.5.0 | 58.0 MB (Open Source) Links: RevPDF Home Page | Github | Screenshots 1 | 2 Get alerted to all of our Software updates on Twitter at @NeowinSoftware
    • Interesting. I'm not using a VPN with my phone. I tried though my home internet (Rogers) and my cellular internet (Telus) and both trigger the dialog above.
    • Three days after Anthropic launched Claude Fable 5 as the most capable AI model it had ever released to the public, the United States government ordered it switched off — and now the company is refunding customers who paid to use a product that vanished almost overnight https://www.techtimes.com/articles/318342/20260613/us-government-pulls-anthropics-fable-5-offline-now-come-refunds-vanished-ai.htm  
    • Microsoft fired the team and replaced them with AI and this is what you get.
  • Recent Achievements

    • Week One Done
      agatameier earned a badge
      Week One Done
    • One Month Later
      agatameier earned a badge
      One Month Later
    • Week One Done
      ssd21345 earned a badge
      Week One Done
    • Contributor
      MarkHughes4096 went up a rank
      Contributor
    • Dedicated
      jordanspringer earned a badge
      Dedicated
  • Popular Contributors

    1. 1
      +primortal
      507
    2. 2
      +Edouard
      175
    3. 3
      PsYcHoKiLLa
      139
    4. 4
      ATLien_0
      90
    5. 5
      Steven P.
      76
  • Tell a friend

    Love Neowin? Tell a friend!