My Computer freezes with most games

[Brennie26]

Hi
I used to run my computer on XP service pack 2 and encountered no problems but I recently changed to Vista and noticed that most of my games were freezing my computer forcing a restart.
I then changed to windows 7 and I'm getting the same freezing.This is starting to do my head in.Has anyone got any idea what the problem may be. here is my system information.
Any help would be greatly appreciated.

 

[Route44]

The 9400 isn't a very powerful gaming card. Did you update the card's drivers when you changed to 7?

 

[Brennie26]

Yeah I Updated all my drivers.starting to think it might be my motherboard.

 

[vectorsigma32]

ur video card is a problem XD

 

[bluestreak95]

vid card yup yup