Welcome to Syschat!

By working drive I take it you mean one you are not having trouble with. This could be one of a few things and is going to have to be a lot of trial and error , basic fault finding and patience I'm afriad.

Have you had the 160GB drive working as a master or slave in another PC?
If yes, can you put it back and see if it works? If it does work then format it in this machine and then set it up in the new machine as a second drive. If not....

It may be a knackered cable, change the IDE cable and check to see if it works. If not....

Also check that all the pins are intact on the drive itself. A missing pin could be the cause of the drive not being seen correctly.

Finally check the setting in your bios are set right. Just plug the drive up and change your bios settings to "optimum setting" or similar (you can change them back later).

Try this and let us know how you get on and see if you need any more ideas...