I may need more information.
What kind of crash is it. (BlueScreen?) (Back to Desktop?)
If an error message appears on your desktop, please tell us Error ID
This problem just arose. Have you played games on your Windows 7 Before? Because mine started crashing when I had windows 7.
Did anything else recently happen to your computer?
Could you Run RealTemp Program and measure it during the gameplay? Or did you already do that.
Do you have another computer compatible with your graphics card? If yes, can you test it with that computer?
Try a registry cleaner, it may be harmful to get freeware ones. I recommend Norton.
Try Error Checking (rightclick C:/ -> properties -> Tools
Windows 7 also has some other curing things.. I forgot what i went through.
Do any other games work? No not solitaire i mean 1 gig+ games.