Need help..plz..

hello.. i'm newbie here..

here what happen when im playing game:
1. cpu restart automatically
2. the game crash (error log report)

i found a dead end in solving this problem..it happens many times. every time the problem occured i went back to the manafacture but the problem still not solved. this is my cpu spec:

MS7550
ati HD 4670 cross fire (but i only bought 1 graphic card since i dont have much money..is this could lead to my problem?)
amd athlon X2 2.7GHz

Complete system specs please, including power supply make and model. Use furmark to test your GPU to make sure it isnt getting too hot, use prime 95 to do a stability check on your CPU, and download and boot off of a memtest disc to check for memory errors.

Did you recently upgrade something in the system? New hardware, new drivers, install a new program?

If you really do only have 1 card and yet have it set to crossfire that may be causing issues, but if you just mean your card is listed as crossfire capable then that is fine as almost all ATI GPUs are crossfire capable.