-> You mean to say I merely need toggle the IDE channels 0 and 1
-> to disable and install an PCI Ultra-ATA-133  card to get the best
-> out of an ATA-133 hard drive?
-> That would be pretty darn cool!!!

IF you find the place to disable the On Board IDE controller it is just
that simple.

-> Not a problem, spare bay in the case however I wonder if
-> the H.P.'s power supply is up to the task.
-> Thanks again for all the help.

 Adding a second hard drive it the rest of the machine is as built as
far as drives go I would not expect a problem. NOW if you load it up
with 5 Harddrives and a DVD drive in addition to the CD drive like I
have done you mostlikely will have a problem.
On their Home Machines HP installs the smallest PS possable. 
I set up a Mini Tower Case HP Pavilion for a senior citizen that had a
100 Watt PS
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