hi there Truckie
Have you looked at changing the master and slave settings? Dunno what you know bout them, but I'll explain them anyway

!
If you have two drives both on the same IDE cable, one of the drives has to be set as a master, and one as a slave, this is usually set by changing the position of a small "jumper" pin usually located next to the power plug!
I assume since you already have a 9gb hard drive in your computer, that one will currently be set to master, so you're going to want to set your new one as a slave.
The HD should indicate somewhere as to where you have to place the jumper to make it a slave, if not, i guess you can blame HP for not showing it

lol
If you need any help with this still, I'll be happy to try and help you out!
cheers!,
om3ga-