Installation fails on Ampro Mightboard 800

[Rod Morgan]

FreeBSD 6.x won't install or run on my Ampro Mightyboard 800.  
Installing from Known good CD's with versions 6.0. 6.1 and 6.2Rc1 all 
generate the following error after present [Enter] at the menu prompt.

Start screen output
............
Select option, [Enter] for default
or [Space] to pause timer  8


int=0000000d  err=00000000  ef1=00010006  eip=00021982
eax=0002197c  ebx=00000000  ecx=c0000000  edx=00000000
esi=00000200  edi=0006a770  ebp=000924ac  esp=0009c47c
cs=0008  ds=0010  es=0010    fs=0010  gs=0010  ss=0010
cd:eip=0f 32 0d 00 01 00 00 0f-30 0f 20 e0 83 c8 30 0f
       22 e0 b8 00 b0 03 00 0f-22 d8 0f 20 c0 0d 00 00
ss:esp=8c 95 00 00 00 10 e5 00-00 20 e5 00 00 d0 03 00
       00 00 00 00 00 c0 03 00-00 00 00 00 00 10 e5 00
BTX halted
............

This board has an Intel Celeron Processor, 512Mb RAM, a Seagate HD and a 
Sony CDROM. It uses a BIOS from General Software dated 5/11/05.  ACPI 
and APM have been disabled at the BIOS level.  The same configuration 
successfully loads, installs and runs NetBSD 3.1, CentOS 4.4 and WindowsXP.

Connecting a working Freebsd 6.1 disk generates a 'Fatal trap 9'.

Start screen output
............
Fatal trap 9: general protection fault while in kernel mode
instruction pointer    = 0x68:0xdd4
stack pointer          = 0x28:0xfd0
frame pointer          = 0x28:0xdc5
code segment           = base 0xc002d000, limit 0xffff, type 0x1b
                       = DPL 0, pres 1, def32 1, gran 0
processor eflags       = interrupt enabled, resume, IOPL = 0
current process        = 0 (swapper)
trap number            = 9
panic: general protection fault
Uptime: 1s
Automatic reboot in 15 seconds - press a key on the console to abort
............

I'm stumped and looking for suggestions.