Originally Posted by pilotbrian0

If you have the 18 gig card and are using a raid card separate from the motherboard (you plug into a isa or pci slot) then it doesn't matter as the motherboard will only see a 18 gb harddrive.

If it is an onboard raid card (you plug the drive straight into the motherboard) then you may run into trouble but it is unlikely. Typically what happens is additional platters or clusters are simply not recognized so your drive will appear as a 32 gigabyte drive.

As to the backing up, you'd have to ask someone who is more knowledgeable about such things, as I have never tried to do anything close to a full backup. I copy my documents to a dvd and reinstall.