Hi all..
I got the similar issue.
Got a Dual PPro machine(same mobo as Gary, ECS-P6FX2-A), Diamond Fireport Scsi card and ATI video card.
Boots up fine on UP, but hangs at, what I first thought was the Initialisation of the SCSI driver, however, on UP it can been seen that it tries to setup the APM bits, and then something times-out and the machine is dead in the water.
When Using the SMP kernel, the apm does not find the BIOS for it (tried both on and off in the BIOS), however, on UP it does, and then boots.
As to Bill's Issues with the network card, well i found that in Red Hat (which is what a lot of esmith is based on) won't detect ANY pci device with SMP kernel and the BIOS has "PNP OS = YES" set.
When I change to "PNP OS=NO" works first and every time.
Hope this gives some inspiration to ppl at this late date.
When I have worked out WTF is going on with my system then I will re-post here with what I did.
AM