Make sure that the HDs are set up as either Master and Slave (if on one cable), or as Primary and Secondary Masters (if on seperate cables).
This can be controlled by the jumper settings on each HD. There is usually a description of the settings on the HD label just over the Jumper slots. You can also go the site of the HD manufacturer for both HD test software and Jumpering instructions.
There is also an alternate jumper setting that enables "cable select", which lets the position of the HD on the cable determine the operation of the jumper (as primary or secondary)
Make sure that at least one of the HDs is connected to the end connector on its cable (preferably the one you hope to be the ''C'' drive).
I have a EPIA VIA motherboard that I'm trying to put 2 30gig HD in. The bios shows the 2 HD's. I've reformatted them and unreformatted them and either way XP won't load on either one??? I read the entire manual and can't figure out what jumpers I'd have to change. I don't see any that would have anything to do with that. The machine originally had Linux on it and I put XP home edition on it. So it has already run an XP program?? All it does is say XP will now check your machines config and then nothing! I even tried to reload Win98 on it and it freezes up as soon as the program checks the machines configuration. Any ideas - I'm at my wits end. Thanx.