Welcome to the ATF.
Do you have both cables connected to the drive properly. Sometimes it seems that the power connector is plugged in all the way and it really isn't or one of the contacts can get pushed out. And if you're using an 80-wire data cable, it won't work unless the blue end is plugged into the mobo.
. Other than that, you need to set the jumper properly. M if it's the only drive on the cable or S or CS if there was already another drive there and what its jumper is set to.
.bh.