Hopefully this will help...
The motherboard in the test system is an Intel Desktop Board D845GRG, so without CPU-Z i presume its an 845G chipset. Info here: http://pixel01.cps.intel.com/design/motherbd/rg/

Looking back at my iso's, i've tried:
(1) Leopard 10.5.2 Leo4All Vers. 3 (Intel & AMD) (Boot problem, panic @ EFI)
(2) Leo4All 10.5.2 Universal AMD/Intel (SSE2/SSE3) (Boot problem, panic @ EFI)
(3) Leo4AllV3, Patched with Leo4All v3 pacth 10.5.3 by JaS (Install OK, reboot on startup)

Iv'e read somewhere that it could be the graphics card? If this is the case i have an AGP ATI X1650 512MB i could try... Although it would have to be pulled out of my media server so ideally i'd like to leave it alone. I do also have a 2.4Ghz P4 system that presumably supports SSE3 with a Gig of RAM and an NVidia 5200 256MB, but again this is a media client so ideally would like to leave alone if i can.

I am next going to try iPC 10.5.6 Universal PPF5 Final.

Kind regards,
James