Year Long Stuttering Glitch Resolved!!! (Drive reverts to PIO mode)

[Pumpkinhead]

I've had a problem with stuttering in SageTV playback which has been reoccurring about once every 3 weeks, and this has been going on for a year or so. I have a temp fix, but it comes back in a few weeks. Sometimes it causes little audio cutouts or even freezes the playback as well until I hit stop and restart the playback. I'm using Windows 2000 SP4. And my video drive is a fast drive using UltraDMA which I tested at about 30MB/sec.

The problem comes suddenly out of the blue one day, but it never goes away on its own. Sage will be working fine one day, then have jitters the next when nothing else was touched. Reinstalling Sage & rebooting did NOT affect the problem. Restoring my Sage folder from a backup folder did NOT affect the problem.

I first resolved it (temporarilly) by going to my ghost backup drive. But that was a big hassle, so before it happened, I backed up the system state, and then simply restored the system state when the problem surfaced the next time, and I was off to the races with smooth playback again. When the problem reoccurs every few weeks, I've just been taking the easy way out by restoring my system state. It takes several minutes to complete, and reverts settings on unrelated things I may have changed since the last backup, so finally today, I decided to see if I could troubleshoot what was causing this problem to either "prevent it" or come up with a "faster" way to get things back and working without having to do a full system state restore. I was pretty curious what was causing it, so finally I took the challenge instead of taking the easy way out.

I've now found a better solution afer running some utilities and comparing my registry before vs after the problem showing up. I've never seen this particular reoccuring issue & solution mentioned on this forum before. Cutting to the chase...

What is happening, is that after Windows detects a total cumulative 6 errors (such as timeouts or CRC errors), the controller reverts to PIO mode. The GUI inteface states DMA, but it's actually using PIO mode. Here is more detail at Microsoft site:
http://support.microsoft.com/default...b;en-us;817472

With Windows 2000 (SP4), there is no download available to fix it. The problem is that if the drive takes longer than 4 seconds to spin up, it will get a timeout error. So apparently this happens intermittently on my system, and after 6 errors over the next few weeks, it shifts to PIO mode and stays there even after a reboot. There is a hotfix that can be requested from MS that changes it to 10 seconds to get a timeout error when accessing a drive. For XP it's already 10 seconds, plus XP will require 6 "consecutive" (rather than "cumulative") errors before it shifts to PIO mode if you just install XP SP2 & make a registry edit noted in the MS knowledgebase article.

You can't fix this by changing a DMA setting in device manager because it is ALREADY showing DMA there. You won't find this on Microsoft's site, but I've found an easy way to fix it, and it is to simply export a correct registry key:

For me, this was changing

SlaveDeviceTimingModeAllowed 0x00001f

to

SlaveDeviceTimingModeAllowed 0xffffffff

then rebooting. So now, when this problem rear's its ugly head, I can have it fixed in 60 seconds.

MasterDeviceTimingModeAllowed should also be 0xffffffff, but my Sage drive is a slave device, and that's where I was seeing the problem.

Microsoft has a workaround of uninstalling the driver using device manager, which is better than my previous method of restoring the system state. I would request the hotfix from Microsoft, but it just happens that I'm about to switch to XP on the system anyway.

Other than this intermittent time-out error with the drive spinning up, I am having no problems at all with the system or hard drive.

Anyway, maybe someone else will experience this issue.

[steingra]

Originally Posted by Pumpkinhead

What is happening, is that after Windows detects a total cumulative 6 errors (such as timeouts or CRC errors), the controller reverts to PIO mode. The GUI inteface states DMA, but it's actually using PIO mode. Here is more detail at Microsoft site:
http://support.microsoft.com/default...b;en-us;817472

I had that same exact thing happen, and ended up finding out after a lot of searching on google about Windows changing the IDE controller transfer mode. Im glad you found the fix. It certainly helped me around the problem.

I used to put my laptop to sleep instead of shutting it down completely. And this was what caused it to happen. For whatever reason.

[stevech]

I hope this does not happen in XP.

BTW, why run Win 2000?

[Pumpkinhead]

Originally Posted by stevech

I hope this does not happen in XP.

It can happen in XP, but less likely, and you can take steps to reduce the likelihood even further. I commented on the XP difference and linked to the relevant MS knowledgebase article in my previous post on how to do this with XP. It's somewhere in the middle of my earlier post.

Originally Posted by stevech

BTW, why run Win 2000?

The system is a dual processor system running a 6 year old installation of Windows 2000 Pro fully loaded with dozens of apps. I still use it for other purposes in addition to its PVR functionality. Other than this problem with the SlaveDeviceTimingAllowed, which is now resolved, it has been rock solid in spite of being fully loaded with a lot of software, albeit slow booting up. I can't remember the last time the system crashed/blue screen, it has been a long time, probably over a year ago. So I figured, why fix or upgrade something that is working so well?

I am going to go ahead and convert to XP, but that's because I'm migrating everything else to a completely different system, and I want to simplify & speed up my PVR system by doing a clean install of XP & Sage 5 and avoid using it for other applications.

In my previous post, I should have said a registry "import" for the quick fix, but the requestable Win2k hotfix from MS would be a longer lasting fix.