I really appreciate everyones help. I've reset the bios Max CPUID to disabled and loaded optimal settings but ,you've guessed right, it's still the same. I've tried this on a clean install of Vista and XP pro SP2(not all the suggestions as im on my vista drive) Ive updated the bios to 1.80 and still no joy. I think this is going to be one of those weekends when my mrs hates computers.