This problem has lead to a complete lockup of this machine, through a torturous path, too much so to detail here. Now I have a new machine using an Asus P4P800-E Deluxe, with 1GB RAM,320GB disk and an Asus graphics card, running MSWinXP Pro, which will not boot from a bootable floppy, from the XP setup disk or any of the emergency restart disks I had prepared. There is no last good configuration any more. The various disk lights come on, the keyboard lights flicker but absolutely nothing is received at the monitor. There are no post beeps.
I suspect the BIOS has been wiped on the motherboard, though I did nothing which could be expected to do that. Any ideas on how to get started again?
I have another very similar MB [Asus P2C800=E Deluxe], populated with CPU, 256MB of RAM etc which I can scavenge. Or I could just build up the other machine and see if I can recover something from the disks