There's this spyware app that takes over your desktop completely, it's a real pain - sets your wallpaper to a fake bluescreen popup, and disables access to the desktop properties.
I'd love to meet a malware coder, just once...
...Heck I'd even travel for it, just sell his major organs on e-bay to cover the cost, problem solved.
The abscence of any warnings is what leads me to think it's software, really any decent motherboard would warn of overheating. If the GFX card has it's own fan power input, then that might be an issue - really that's best on it's own power line, like not sharing with a HD or CD/DVD rom, my card has a bolt on fan added, which has this problem. Heck, a good root around inside the PC might resolve it, like make sure everythings securely bedded, especially the memory and GFX card. It might just be that you've knocked something loose when installing the card - lost count of the number of times I've done that.
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