oops,... apparently it is not that simple. Maybe first try it on a test disk. The first thing to do is to write down on a paper where your partitions start and stop (cylinder, head and sector). Once you've wiped the MBR, you have to rewrite it and to recreate your partitions without formatting else you lose your data for good. I can't try it myself right now as I have boot manager in my mbr and it racts differently. And there is nothing to gain from it. Wiping the MBR is not deleting it. I mean you don't regain any disk space, as already stated by McTavish. It is playing with fire, big risk, small reward. And it's got nothing to do with this forum. Edited... I just tried, this is not for the faint harted. Also no warranty by me (multiboot or XP not starting). Wanna wipe it ? -> Wipe the MBR with "E" (erase), rewrite it as Standard IPL, and press F2 (get "partition was written" message), go stand on each partition and press F2. Reboot and you'll see ...no difference at all.