|registry mechanic. registry fixers are never recommended. They cause more damage then they fix.|
Sound more like hardware failure though since you had the same thing happen with booting the xp cd.
Might start with opening the case, blowing out the dust. Try a different keyboard. Same results booting from the xp cd [assuming you changed the boot order in the bios to boot cd/dvd first] I would reseat the ram and any cards in the system.
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