Yesterday I tried overclocking my C2D for the first time, following a guide from one forum. The actual overclock seems to be working fine, no errors, lockups or overheating. But after I changed the settings in BIOS, the computer now soft resets by turning itself off for a few seconds, then it comes back up. Also the Hibernate option suddenly popped up in my Vista shutdown dialog. I only touched the BIOS settings in the CPU configuration a Jumper free configuration (the frequencies). What could be causing this?