How to check if the GPU is in trouble?

[nicobonetti]

Hello I have my DELL DIMENSION 9200 from 2005 that have stopped working: What I noticed is: - when the bios screen is loaded I see mixed to the usual screen characters (white on black) lots of commas "," in between (this is what makes me think that the problem may not be the graphic card) - I have dual boot winxp/ubuntu if I boot windows I got blue screen of death, on ubuntu sometimes i get a chessboard like screen full of coloured pixels other times i got a visual error (about graphics) - if i boot windows in recovery mode it will load fine. No visual problems

--what I already tried: reinstall nvidia drivers. Via shell(ctrl+alt+F1) now I m not able to load ubuntu anymore. Because I think the tmp directory got full during re/install - I tried a memtest86 ubuntu boot: but as far as I run it It didn't find any error

Well at the end I believe that my nvidia 7900GS Is dead and I m going to buy a Sv Sapphire Hd5450. It looks a valid compatible substituted.

But I m also arguing if ever is the Mobo in trouble. So I may waste money in a graphic card

What do you think? Can I perform some other kind of test to diagnose better the problem?