I just installed a third HD(Hitachi Deskstar 1TB SATA) and although my BIOS and System->Disk Drive recognizes it, My Computer doesn't show it. Any ideas?
Don't be afraid to be wordy here. You will save on these "we need more info" posts.
Is it a new drive, or was it working somewhere else? Have you tried a different socket on the MOBO, a new cable, and a different power connector? Can you try it in another system easily? Are you getting something showing up in Device Manager with a yellow question mark?
Go to Hitachi's web site, download there Drive fitness test program, and see what it says. Any errors there, and it is time to look into an RMA.
By far the most likely scenario is that there are no partitions on the drive that Windows understands - probably because there are none at all. Formatting it in Disk Management as above will fix that.
I just reformatted my main drive and WinXP won't recognize the drive again. I fixed it the first time by formatting it in disk management but I don't want to format the drive since I have so much valuable files in it. Is there a way around formatting the drive?