Random reboots and occasional shut downs

Hi! Chaslang suggested I come here after doing all the 'read & run me first' stuff and finding nothing. I am experiencing random reboots and occasional shut downs. I believe these only happen when I'm gaming, Everquest 2 or EA Land. When it logs back on after a reboot, I get a message, 'Your system has recovered from a serious error.' Then I send the error report, to windows or wherever, it usually said it's a driver error On occasion, but rarely it has said memory error, or hardware error. I've done the memory test that they recommend but it's never found anything. I have updated my dirvers but it didn't help. Any help to fix this problem would be greatly appreciated. :confused