If you built it yourself, im with keyclone. Its most likely a heat issue, however most system boards will warn you on the next power up that it had a thermal event. The second most likely cause is some sort of incompatability issue. Update any and all firmware for all components including, Hard Drives, Optical Drives, System Board etc. If its not one of those two thing then its anyones guess unless you can get it to BSOD or get a mini-dump of some sort to run through the analizer tool.



If its an OEM box. Call the manufacturer and dont settle for anything less than a new computer or take it back to the store where you bought it if your inside the return period. Set a standard, don't pay money for something that does not work.