les wrote:
Hello...
I've been stumped about a method to clear the BIOS on
my HDD to the correct setting.

You mean reprogram the firmware. Don't think wdc have new ones, so you
are SOL.

Looking at the jumper bus, I noticed a mysterious jumper
near the slave/master pins, called PM2.

Get the full model number written on your drive (it's not just WD800)
and have a look on www.wdc.com

PM2 is a power management jumper.

--
Adrian C