Ok, I got past the BIOS problems that were locking me out. I then inserted a new hard drive in place of my old primary (I had two physical drives, partitioned to four logical drives. When I installed windows on the new master ide drive at position 0, drive 0 etc. It became drive G and the slave was renamed to C and D. NOT, repeat NOT what I want. My question is this - how does the Windows OS determine the drive letters? I have two IDE buses, with two optical drives on one, and two hard drives on the other. I would like to lose one of the optical drives, and put my old 40G hard drive there. In other words - to have three physical hard drives in my machine. I want to designate the main drive as drive C and I don't care about the others - but the OS seems to do this by itself with no input from me, and it screwed it up!

That seems a bit odd. Windows installer offers the C: drive as the primary location of the OS IIRC and it should have formatted the new hard drive as such, unless you tell it not to. If the drive already exists, then it offers that, if it doesn't it offers to create a parttition for that purpose. Perhaps with your BIOS problems the drives got re-allocated behind the scenes, but only AFTER Windows got installed to the G:| driveYour problem is if Windows is now installed to G: it might prove problematic to rename G: to C: but it must be worth trying. And you'll need to change the drive letters anyway.Control Panel - Administrative Tools - Computer Management, and then the Disk Management tab, is where you find the means to change the drive letters in XP but I don't know whether you might compromise the integrity of the Windows installation by renaming the drive. I don't have any experience of using Windows Disk Management, but I knopw for sure you could do it with Partition Magic, but that's payware and if the Windows software does it OK, then you might save the money.Allcott

Strange indeed. Have you checked the jumper on the new drive? and have it set to master with slave present? instead of cable select mode? You can change drive letters easily with Disk Management. However if you have installed programs in it, they might not work after a letter change.BTW if a hard disk and CD-ROM unit are placed on the same cable, the hard disk would be preferred to be master and the CD-ROM as slave, although they can still work in reverse. It is not absolutely necessary to have a master, a slave unit can still work alone on the cable. In order to obtain better performance, if possible, place your hard disk on the first IDE channel (usually labeled on the motherboard as IDE-0) and the CD-ROM on the second IDE channel (IDE-1), therefore using two separate cables and having only one device connected per cable - this will help improve transfer speeds and overall computer performance when hard disks and CD-ROM drives are used simultaneously.