HELP please HELP

[cyclotic]

hi there im having abit of truble with my new pc i built it seems to work fine until i play games like halflife or battle field 2 it runs fine for about 1/2 hour then the screen just goes black but the system is still running the temps seem fine and the voltages are ok to its kinda strange as it will play call of duty no problems im stuck and it doing my head in.
my system specs are:

abit an8 sli mb
amd athlon 64 fx 57 2800 mhz
2 gig ram crucial ballistix
250 gig maxtor hd (sata)
xfx nvidia 7800 gt gfx card

i would much apprecate it if any1
one can help
oh and thx

 

[tjm4fun]

try a differrent video driver. they change versions almost weekly, and I've see it quite often that it will work fine on one game, but crash, or hang in another, as they can use differrent rendering parts of the driver.