Thanks, so far.
I knew that you can <pause> BIOS while booting up.
When I tried it to give my HDD more time the LED lit up for about 14 sec. Yet BIOS didn't see my drive after that, regardless wether I plugged it as primary slave or secondary master.
When I booted Seagate's '
SeaTools' it saw two drives but only offered up one for detailed working.
MHDD (from DOS shell) saw
something on my secondary IDE but couldn't do anything with it. (pic)

Windows Device Manager sees
something strange where my drive should be. (pic)

Please help me out here.
I'd like to retrieve at least some of the data before I toss it in the trash.
idea: Is there a tool with low-level access (like MHDD) that can copy the files to another disk?
I think they are undamaged, as the drive passed MHDD's surface scan.