I've tried three different video cards in this computer and none have worked as well as they should. Computer specs: .windows xp .Processor: AMD Athlon xp 3000+ 2.16 ghz .768 MB of Ram Video cards i've tried: .ATI Radeon 9550 AGP .ATI Radeon PCI .Nvidia 6200 (current video card) All came up with the same "system stop error." More specifically I start playing World of Warcraft and after an hour or so it freezes. Sometimes the sound repeats itself and then it freezes or it stops for a few seconds and then fixes itself. Most of the time I have to restart it manually but sometimes it restarts iself and shows the same "stuck thread" error. Thanks for any help! .