In the modern hard drive thread, we were only talking about a specific hard drive.

2.5" u320 IBM eServer drives.

I do not vouch for any other SCA hd.

In-fact I have tried other SCA hard disks a Fujitsu one, and another one forget the brand, and neither of those worked for me in vintage mac's

The magic is in the chipset of the drive its self, wether or not they really did follow the proper backwards compatibility.

It just so happens the drives i'm selling for 30 each. they do work outstanding and are fully backwards compatible.