[LPDad]

Question: (it was not clear to me)
When you ran the POWERMAX utility, did BOTH of your harddrives show up??? Was the utility able to see both of your hardrives??
If your C drive does not even show up then I would suggest SWAPPING the 2 drives (making sure you set the jumpers correctly--if your mobo allows it just set both drives to CSEL..makes swapping drives easier)
If, after swapping the 2 drives around, you still cannot see the problematic drive then your next option is to connect that particular drive to another computer to see if it can be seen.

Need to narrow things down a bit. What MOBO are you using (or brand of Puter)?? How old is it?? How old are the Drives??

Does the recalcitant drive SPIN UP when you apply power??? (you should be able to feel it).
Need to narrow things down a bit to actually find the problem... The first step is to actually get the software to SEE the problem drive.