Computer stuff

You have two IDE drives? I thought you had only one.
If you connect both at the same time then set one to master and one to slave.
If you connect only one then set it to master.

But anyway, this corrupt info data looks like a HDD or IDE cable failure to me.
If the cable doesn’t look actually damaged from the outside or very roughly bent then I’d go with HDD failure.
Unless you have a spare cable and find it worth your time to try and switch it.

I have several IDE hard drives but only one IDE slot on this PC.

These hard drives worked rather well until one point. The IDE cable does not look damaged. My suspicion is motherboard.

I have an older PC that still works. Might bring it here to test these drives.

Ah, and all IDE drives show basically the same behaviour?
Then it’s either IDE cable or motherboard.
I don’t think it’s the power supply if it’s corrupt data. Power supply issues would be more like random shutdowns or not booting (parts) in the first place.

Yes, they all show the same behavior.

The IDE cable is actually torn at one place but it’s been like that for ages so I didn’t register it as being damaged.

Tested the hard disk drives on my PC from 2002. They work. So it has to be either the cable or the motherboard. Didn’t bother testing the cable because I gave up on using these drives (too much work.)

Actually, the IDE cable is just split and that shouldn’t be a problem, right?

So it’s probably something related to the motherboard or Bios. Either way, at this point, it no longer pays off.

Should be no problem that it’s split at some point(s).
Old IDE drives are often quite loud and quite slow.

I’m not sure but I think some Linux distros allow to install on the same drive as a Windows installation.
Again, the Windows needs to be installed prior to trying to install Linux. There are some guides out there for this, I think.
It’s a good way to keep old hardware relevant if it’s only for Internet, Office and Video/Audio.