Don't know if this will help but you might have this motherboard:

<a href="http://www.asus.com.tw/mb/socket370/cuwe/overview.htm" target="_blank">http://www.asus.com.tw/mb/socket370/cuwe/overview.htm</a>

Asus CUWE

3 PCI slots..onboard video (i810)..jumper free (hence there are no jumpers, and HP is using a custom BIOS to prevent any major settings changes)..no AGP...HP uses Asus a lot so I'd tend to think this would be an Asus board.

Sorry if it can't help much but you said anything would be appreciated