Bad on-board video, Can't see to set BIOS

Your system will automatically default to the AGP slot when populated with an AGP card. I doubt the PCI strategy will work because of the malfunctioning unit already on the PCI bus. Besides the old 2X/4X AGP cards are a dime a dozen.

Does not have an AGP card (on board ATI Rage) that is "AGP" device.  The video discovery sequence is controlled by the BIOS.

I have installed PCI cards in similar PCs with on board video and, so far, they all have worked.

In other words, been there - done that.

Dalton

Thanks.
  I'll try those ideas.  I already have a loaner from a friend set up, but it's just taking a lot of time to get together.
  I'll post followup questions and/or results as necessary.  It's not top priority, so it's take a while.

> PIII-450 is getting long in the tooth
Yea, but it's is such a great multi-purpose energy consuming, noise making, dust collecting heater!  I keep it around just for one particular client who has some special configuration needs, and a once-a-year task for me (coming up soon).

if you can get it to boot with a pci video card (remove the agp card) - get into the bios and disable powersave options.. also if theres option for energystar compliant monitor... disable

This is a cut and paste from another question that I answered.  Answer was accepted, so must have worked for them.

Actually this is a rather simple and straightforward procedure.

Step 1 - Configure BIOS Settings
Most BIOSes have an Integrated Peripherals section where the settings you need are located.  There should be an Initiate Display First setting.  Ensure it is set to PCI.

Step 2 - Install PCI Video Card
With power cord unplugged or master switch off, install card in PCI slot 1 (usually slot nearest CPU, but check mobo markings or manual).  This should prevent IRQ conflicts.

Step 3 - Connect monitor to PCI video card.

Step 4 - Boot PC
You should now have a display.  Windows XP should load its own drivers for an ATI Rage card automatically.

Step 5 - Disable on board video if you so desire and  BIOS or mobo has settings/jumpers to do so.

If this doesn't work, BIOS is different, or you have some other problem, let me know.

Dalton

Unfortionately unless you can actually SEE the bios it is difficult to set the video boot device.  From this point there are really two options:
Put in a PCI video card and hope it boots to it.  Equally important is to hope that it boots every part from it, there are situations where the main boot sequence (until it starts loading windows) will be on the onboard and the rest will be on the PCI card.  
The second option is to do some research on the particular bios type, this will lead to some hazardous and tricky manipulation.  While I would try to avoid doing this, with enough information about the bios menus it is possible to change a setting or two blindly.  Again, you'd really only feel comfortable doing it if you had another system with the same bios right there to allow you to see what you're doing, but it is an extreme option.  If you ever can see the bios, what willcomp suggested should allow you to eaisly install a video card fine.

Thought monitor was working for awhile and then going off.  If you can't see anything at all, just omit step 1 and go from there.  PCI slot first is default for every BIOS I have seen that allows selection.

Dalton

Youve got an ISA slot. Isa slot video cards can somtimes boot board after faulty bios flashes. Would let you reflash bios or in your case change settings. Old isa cards aren't worth anything you just have to find a few different ones and try them.
Peter