Yesterday my computer crashed and the hard drive running as a slave disappeared. I've tried different IDE and power wires, and the jumpers are in the right positions. This seems to be a fairly common problem but the difference with mine (worryingly) is that the computer doesn't even recognise the slave drive when it boots up. I can feel its running - though it feels pretty hot - and I have no idea how to fix it.

Any help would be much appreciated.

Things that may or may not be useful:
Whenever I change the jumpers to a different position (one that still makes sense) the computer does recognise an IDE hard disk on the next boot up, but doesnt on any after that.
If i set the slave in BIOS from auto to '46' (for a 160gb drive) it boots up and reads the make and model of the drive, meaning the computer is still reading something from it - but still nothing in windows.
I'm running XP and both my primary and slave drives are Maxtors.

Yeah, it does not sound good for that drive. Do you know why your system crashed? You might try something simple like replacing the motherboard battery. They are typically CR2032 (check your manual or the current battery to be sure), and cost about $2.00 at Wal-mart or Home Depot. Be sure to unplug the computer from the wall before removing the old and installing the new. And don't touch the new battery with your fingers - skin oils attract dust and promote corrosion. By removing the battery, you also reset your BIOS so on the first boot with new battery, go into the BIOS, make sure your drives are recognized, and Save and Exit.

This may not fix your problem, but it often does fix similar problems, and for $2, it is worth a try.