I thoroughly 'cleaned' my PC of dirt and accumulated dust recently. This invovled removal of the CPU heat sink and re-attaching it. Also, I've added two additional RDRAM modules. Since then, the PC dies at random - and quite frequently too causing me to lose data (files currently in use - TMP files from Bearshare (a P2P download manager). When this happens, the monitor LED is still on as well as the num lock LED but the PC is rendered inoperable for all practical purposes. The reset button does not work. The XP Scandisk kicks in when I have completely powered down and restarted. It 'truncates' many files - usually the above mentioned TMP files.