I'm using Windows XP with a Radeon 9200 Series video card.

I made a thread here recently concerning this problem, which I originally thought was being caused by the monitor.

My monitor (or any other monitors I've since tried with the computer) will black out randomly (usually after a few hours of running) , come back with a garbled screen, go black again, then show Windows again, but with some further problems like video being unable to play or desktop widgets not displaying properly, until I restart.

After the monitor does its thing, I'm presented with an error message from my video card's manufacturer, ATI.

So I've attempted to completely uninstall and reinstall the video card. I removed the drivers and associated software, restarted the computer in Safe Mode and ran Driver Cleaner Pro's driver and cab cleaners, then reinstalled it all.

But it's still giving me the problem. Just wondering if there's anything more I could do to get it working before I take it back to the shop. Thanks!Does the length of time elapsed before this happens vary, depending on what you're doing on your computer?  Do you have any temperature monitoring capability in your system?  What are the other specs on your system: processor, RAM, hard drives, optical drives, power supply, etc?  

You mentioned taking it "back to the shop".  Did you recently have it in a repair shop?  Why?  What did they do?Yes, the length before it happens tends to vary. The error often occurs when I'm using video, but sometimes it will do it with just Soulseek and/or Firefox running.

I've got a temperature monitoring program called Speed Fan. The problem happened again about an hour ago and I've since restarted.
It tells me this (the temperature values fluctuate, so I'll approximate):

Fan 1: 1918 RPM
Fan 2: 2519 RPM
Fan 3: 0 RPM

Temp 1: 23 C
Temp 2: 38 C
Temp 3: 21 C
HD0: 41 C

All the fan speeds are set to 100%, but the 0 RPM value for Fan 3 makes me wonder if a fan has stopped working. Not SURE off the top of my head if there's two or three fans in the tower. But the temperature doesn't seem too effected by it.

As for the computer specs, it's Windows XP SP2,  the processor is an Intel Celleron 3.33GHz, the RAM is 1 gig, my main drive is referred to as an HDS722516VLAT80 (153 gig), and my external hard drive (which I watch a lot of videos files from) is a Samsung HD300LD USB Device (279 gig).

My motherboard died mid last year and it was replaced, along with the video card, power source and sound card. The system was formatted.

Not entirely sure of the voltage or model of the current power source. The guy at the shop told me that the previous one didn't have a high enough voltage and that the new one would run it all comfortably.The 0 RPM value for Fan 3 does not necessarily indicate a non-functioning fan.  Most likely, it's just a fan for which SpeedFan can not detect the actual RPM.  I have SpeedFan installed and I have the same situation, and I know all my fans are working.  

None of the TEMPERATURES SpeedFan is reporting for you indicate any temperature problem.  In fact the 21C and 23C temps are so low that I wonder about their accuracy.  Nevertheless, I suspect none of those temperatures relate to your video card; in other words, I think SpeedFan is not giving you a temp for the video card, just as it does not in my system.  I believe my motherboard and/or video card aren't sophisticated enough to provide that info to SpeedFan, and, even if it was, I don't know for sure whether SpeedFan would report that temp.

So, I don't think we can entirely rule out a temperature problem with your video card.  Do you know whether card has its own fan?  Can you open your computer can and take a look?  

Perhaps we've so far OVERLOOKED one possible, perhaps obvious, CAUSE, which is the monitor.  Can you test that monitor by using it on another computer?   Can you tell whether your computer is completely freezing up when the monitor screen goes black, or is it just the display part of your system that's malfunctioning?  How are you restarting when the monitor goes black/blank?Just opened up the case and the card doesn't have a fan of it's own. There's just the power source fan, motherboard fan, and a general fan at the back.

The voltage for the power source is 350W.

The monitor was what I thought it was initially, so I've already tried out two other monitors on this computer and had the same problem.

The computer seems to momentarily freeze before the screen goes black and it does it's thing.
After that an error message comes up from ATI's VPU Recover saying:
VPU Recover has reset your graphic accelerator as it was no longer responding to graphics driver commands.

Once it's regained it's footing, I'm able to shutdown normally from the start menu.ATItool will show the video cards temperature if it has a sensor
http://www.techpowerup.com/atitool/

The temp should be under 50c

Otherwise a memory glitch on the card or in your ram may be at fault, or maybe write combining is at fault, you can disable write combining in display properties/advanced/troubleshoot/disable write combining.

Do you have the latest direct X drivers installed?, the 9200 is not a direct x 9 card I know but the newest direct x is more than that, it is backwards compatable and contains other updates to improve stability. Quote

Just opened up the case and the card doesn't have a fan of[highlight] it's[/highlight] own.

Once it's regained [highlight]it's[/highlight] footing, I'm able to shutdown normally from the start menu.