Comp has trouble identifying new harddrive?

Screwed up XP on my old harddrive. Got a brand new harddrive.

Initially had some difficulty getting the computer to recognize the new hard drive; I had apparently plugged it in to the wrong slot on that cord, if memory serves. Switched the plugs, worked fine.

Installed windows. Successfully slaved the old harddrive to the new one, where I could use both in windows XP [Old drive became "F:\"]. Started installing a handfull of things, namely drivers and a couple games. Was running fine for about a week. [If it matters, it was largely still running during that time, with a handfull of shutdowns due to having to install stuff like Direct X.]

Ten minutes ago, I decide I wanna play morrowind, which is located on the old drive. Exited out of the game I was playing, went to My Computer... and the slaved drive wasn't there.

Figuring it was a glitch, I rebooted the computer, only to find out that it isn't recognizing the new hard drive again.

Attempting to reinstall windows [again] reveals that windows is in fact still there on the new hard drive, which doesn't make much sense to me; how can BIOS not know what's attached to it, yet XP can read from it?

Anyway, I have two questions;  one of which being WTF.

The other question is... well, I was told to delete the windows directory on the old harddrive. I didn't.

Could having the old instalation of windows on the old [slaved] drive messed with the installation on the new drive?

No offense; I said the drive was fucked-up due to the 15/16 head crap.  It's been a long time since I've had to worry about CHS (cylinders, heads, sectors) settings for hard disks, and believe me, I don't miss that at all.  :^)

As for IDE0 and 1, I suggest separating the drives so that they aren't on the same controller.  If you have two IDE controllers on the motherboard, then you can connect up to 4 IDE devices.  Since you can just move them around a bit, then got from (I assume) this configuration:

IDE0: Master (new hard disk), Slave (old hard disk)
IDE1: Master or Slave (CDROM)

... to this:

IDE0: Master (new hard disk), Slave (CDROM)
IDE1: Master or Slave (old hard disk)

Now, we must address the "driver" thing.  I don't know what you mean.  Are you using some sort of hard disk size-adjusting driver like the stuff from Ontrack?  That might well explain all this fuss.