OK, made some progress on it.
Apparently this is a PIMPED Compaq Portable...
It's got a 386(!) processor card, a presumably large amount of memory(wouldn't be surprised if it was 640k!) and, oddly, a hard drive card... minus the hard drive. That was what was causing the 1701 error, and when it's removed it displays "Diskette Error, please press any key to retry."
Sadly, it appears that the keyboard doesn't work, as even when I insert a (blank) diskette nothing happens when I press the keys. No access of the floppy drive or anything.
Anyone have any experience with these?