Question : multi colored screen crash

Morning EE, Just a few days ago i had a crash to a multi colored screen while gaming. I can use this pc all day with no problems until i game. This morning it did it again. As a test I played several different games with the same result. I can't swap the memory because this is the only set of ddr3 I have. . But I can try one stick & run memtest in a while. There are more than enough fans in this case & my temperatures are fine. I'm going to try another video card now. Strange thing just happened, the usb for the keyboard just died. I tried another new keyboard, not. It does work in all the other usb's. Could this be a mobo problem? Thanks for your time. Ed
Windows 7 ultimate
EVGA 790i  mobo
intel q9400 cpu
4 gigs Patiot ram
BFG 280 oc video
x-fi fatality titanium sound
ultra 1000 w power
seagate 1tb hd
pioneer blu ray burner
thermaltake spedo advance

Answer : multi colored screen crash

Are you certain about the temperatures?  How are you monitoring them while you are gaming?

Might be a PSU issue but it sounds like the graphics memory more than the system RAM.