I have done this many times and never lost the data on the slave drive, you just need to be sure that the drive you are formatting is the primary drive,C: I read a post on another forum where a person formatted the wrong drive and lost all his data. Just to be sure you could always open the case and unplug the slave drives power and ribbon cables.
I just built another PC for the wife. Exactly like mine, Shuttle motherboard, AMD 2400+ XP processor, 512 Meg RAM. Her machine boots in about 30 secinds, mine takes almost two minutes.
My machine has a slave HD, 20 Gig, with most of my "saved stuff". I'm thinking about reformatting and reinstalling XP on mine and doing a little clean up, hopefully to get mine to boot faster.
My question is will all my saved stuff be lost on the slave drive? I'll put all my email stuff, favorites, etc. on the slave if it'll be intact after the format.

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