I'll take that disk boot back.
BiosCentral has a text with CMOS addendum but it can be something else.
Surely network boot is the last in line and system think it must put up something.
Disabling all but HDD boot should clear things up, putting all possible texts on would also help.
Does the ddrescue quote mean that the original drive has crashed?
If so then all bets are off with it.
amyk's approach is what should happen next.
Use spare drive and put there a Linux.
I'm usually using Lubuntu, it's bigger than CD now but older version shouldn't be a problem.
You don't need to boot it up, boot manager is enough, it's timed by default so press up/down and stop the clock.
If you get there you can be pretty sure that the disk interface is working.
If drive is too big it can be clipped, usually.
Consult HDAT2 or similar, Host Protected Area is the thing and set max address there.
Be also sure that drive jumpers and its cable are not conflicting.
Cable in question usually has master and slave stamped to its connectors.