computer restarts once in a while

I get this error

STOP:0x0000009C (0x00000004, 0x00000000, 0xb2000000, 0x00020151) "MACHINE_CHECK_EXCEPTION"

My computer just restarts. I"ve never been on the computer when it happens I just here it restart. the computers idle when it happens. all my hardware seems fine. And it's all new stuff. Temps are fine CPU 42C MB 34C That's the temp under a load doing a nvidia performance stability test . ASUS (M2N-E SLI) MB, ROSEWILL (RD 600N-2DB-SL BK R) PS, CORSAIR (TWIN2X2048-6400 R) RAM, EVGA 2x (e-GeForce 7900GS KO 256MB) in SLI mode GPU, and a AM2 64 X2 5600. Nothing ever overclocked. could it be ACPI? any idea?

 

http://support.microsoft.com/kb/329284

From what I see you have hardware problem related (I think )with memory.Check the memory with Memtest 86:http://majorgeeks.com/Memtest86_d1247.html

Open your case and see if some fan don't work properly.CLEAN the case if it's full of dust.Post what you've done.

PS: and WELCOME to Major Geeks!!!!!!!

 

Cleaning Wise I Just Built It A Little Over A Month Ago.
I Did The Memory Test. Passed Everything. Did A Nvidia Stress Test On Ram, Gpu, Cpu,and Hd For 24 Hrs And Passed. I Changed My Power Scheme From Home/office Desk To Always On And Not To Restart On A Error. It Hasn't Had A Error . I Think It Was The Power Scheme.