Oh, sorry about that. I've just tried booting from the original CD and that makes no difference whatsoever.
I'm already using the latest BIOS available (1008) and the mobo I'm using is the one included in this system -
http://www.asus.com/products/desktop...3/overview.htm
I've got a Celeron 2.2 GHz CPU and 333 speed ram. Don't know if knowing those specs will help at all, but there you go.
I'm making myself a Win 98 boot disk now and will try that in a minute. The DOS 6.22 boot disk can't even locate my hard drive so that's a non-starter. The Ultimate Bootdisk won't even boot for some reason - fairly crucial feature I would have thought for a boot disk!
I also tried opening the case and using different IDE cables. Before the CD drive and hard drive were sharing IDE0 using a two way cable. I've since changed this arrangement so that they each have their own channel and that didn't help either.