UNIX Desktop Questions & Answers

"Old computer" should mean Pentium 3 and older. The P4 requires the operating system to regulate the cpu temperature, and that wasn't added until about 1999-2000.
The oldest release of SCO Unix that I still have media for is version 3.2.2, published June 1989. At the time we ran it on a Compaq Systempro with two 386 processors, two 387 co-processors, and four 100mb IDE disks (RAID 1). We also had a 24 port Consensys multiport serial card with its own processor.

Thanks for the info cjcox, I'm currently in Scotland though. My house is littered with old computer parts people were throwing away. Like a old Commodore 64 (not working unfortunatly) that I salvaged from the rubbish tip from my old high school.

I doubt a laptop or modern desktop would be accepted by any early 80's UNIX. PCI wasn't invented at that time so an ISA or EISA bus would probably be a requirement for the OS. Perhaps booting some kind of 5"1/4 diskette miniroot ...

One way around the old hardware issue, is to use an emulator like Bochs. It can be build to emulate an IBM AT and more. I have used it successfully for this purpose on a number of occasions.

Just recently scrapped my last 386 laptop, a dual boot DOS/Xenix 2.3.4 running on a 10/10 HD split IIRC. In its place is a dual boot 486 with DOS and SCO 4.2 unix.
Although SCO wanted specific hardware I was able to put their stuff on a bunch of hardware they probably never heard of and probably wouldn't have supported, if they supported anything. ( ongoing snipe)
Whatever you choose, it probably will need ISA bus and a MFM set, or possibly a SCSI set, although SCSI controllers for that vintage are going scarce.