Computer won't boot - video problem?

this is long.  perhaps it didn't need to be this long.  Please read it anyway.

So, I have a Radeon AIW 8500DV, on an ECS K7S5A board, Athlon XP 2000+, 1 gig of RAM, blahblahblah. Connected to a lovely mitsubishi LCD, the model of which i couldn't tell you at the moment, since I'm at work and it's not.  Running Windows XP SP2

Anyway, my problem.  I was in Windows yesterday, watching a video (the card was in theatre mode, so i saw my desktop with the windowed video on my monitor, but full screen video on my tv).  Suddenly, the computer locks up, and the display is distorted hardcore so that it looks something like this.

http://i17.photobucket.com/albums/b62/xandir/050804-0043.jpg

I thought "hey, that's lame" and rebooted.  The system hung during boot, with a black screen.  Rebooting fixed it.  It worked okay for a while, but in the process of that crash, an external drive had gone wonky. (It's not relevant to the problem in question here, but is necessary to mention, for timeframe).  I mucked around with it for a while trying to fix it, and then the video fucked up again.  Booted back into windows no problem.

At this point, I decided I needed to jump into knoppix to fix this drive, so I booted from my knoppix live cd, and did stuff for an hour or two (it's about 4 hours since the original graphical distortion/system lock up).  While running dosfsck on the drive, the system hung and the display distorted into those vertical lines again.  Rebooted back into knoppix, no problem.  Decided after a while that I needed to be back in Windows, so I rebooted.

Then it all hit the fan.  First, I could get the XP loading screen, but when it tried to load the Welcome screen, it would hang, either with a black screen, or with those vertical lines, or sometimes "check boards".  The more I tried to reboot (hoping it would randomly work at some point), the faster this crash/distortion occurred.  Next, it would happen when switching to the XP loading screen.  Next, it would happen immediately after the memory test.

I left the computer off overnight, and tried again.  I thought maybe the video card was just overheating, as it was hot, and the computer had been on all day.  This morning, I tried again, this time booting into Knoppix.  It got as far as loading my window manager, and then the screen blanked and the system hung.  After that, it was always mid-boot at best, immediately after the memtest at worst.

So, my question to you: wtf is wrong?  Did my AIW crap out magically?  Is it a mobo/RAM problem?  Is it just heat, or is the card actually fucked?

I can't find anything on google, most things with "Vertical lines" end up being display corruption, but they can still boot up, and stuff. If I could do that, I'd be so pleased, right now.

Anyway, thanks for your help.

Hunh.  Those lines remind me of refresh problems, though your problem is clearly more extensive than that.

I think that >>4 is right.  It's time to test everything with a known-good system.  I've never actually had the SMART technology work for me, so it doesn't surprise me that it didn't say anything, but I'm still mentally suspecting the power supply of frying other components.

Oh, and when you *do* tear things apart, don't neglect to consider the possibility of a fan causing the problem.  It took me months, and an RMI'd proc & mobo, to figure that one out on my computer a few years back.  It, too, was crashing as it tried to enter the BIOS.  When I had the chassis fan plugged straight into power instead of the motherboard chassis fan power/speed regulator, though, everything worked great.  I'm still using the same mobo and fan today.

Earlier I might have suspected a reinstall might help, but the timing of your frequent crashes makes that less and less likely.  I think you're looking at some sort of progressive hardware issue.