The games i play are Warcraft 3 the Frozen Throne which is a 2003 game and the other Battlefield Bad Company 2 , and it does it just when i am surfing the web too ,so i am sure it is just a virus or just overheating

I am sure it was just overheating i opened the side and put a fan blowing in it and it hasn't turned off yet ,i noticed it was full of junk and i cleaned it the best i could but it still needs cleaned. THanks for the help JDB and Colleen

I have a Pc. Its custom built and has a 9600 geforce NVIDIA graphics card it has been working fine for the past 2 years it just recently started to turn itself off , it has 3 fans in it one on the top of the tower case one on the back ,and one right on the graphics card itself. Over heating sounds like what it is , it just seems weird it just started. if there is any other reasons please share them.

Thanks, Colleen much appreciated!