ASRock 775Dual-VSTA mobo bios troubleshooting - error 6B38

[waylo]

I'm concerned my mobo above has finally died.

It will boot and the BIOS starts to display.

It then freezes with the status code 6B38. Cannot enter BIOS settings at all. It looks almost exactly like this (only this is a slightly different board):
http://itparanoid.blogspot.com/2008/08/asrock-4coredual-vsta-bios-error-6b38.html

Through some google searches, some other users recommended unplugging all USB items, or cutting all power to the board. One of these must have worked, because it finally got past this point and continued booting into Windows...

For a few times. Now, it's right back to where it was before. I've pulled all USB items and cut the power repeatedly, and it's still stuck.

Any idea where the trouble may be? My guess is that it's trying to initialize whatever 6b38 indicates, and due to a fault, it is stuck there.

Code 38 I've found =
"Initialize different buses and perform the following functions: Boot Input
Device Initialization (function 3); IPL Device Initialization (function 4);
General Device Initialization (function 5). Function 3 searches for and
configures PCI input devices and detects if system has standard keyboard
controller. Function 4 searches for and configures all PnP and PCI boot
devices. Function 5 configures all onboard peripherals that are set to an
automatic configuration and configures all remaining PnP and PCI devices."

RAM:
I had 2 sticks of RAM dual-channel memory booting, but I've pulled and reset them in all permutations with the same effect.

 

[waylo]

After a few days of bizarre non-posting behavior, pulling everything out (USB and PCI cards), putting everything back in, rearranging memory sticks, the system has revived itself.

NO IDEA what happened. Maybe a CMOS corruption. I was just about to reset the CMOS when I figured I'd try it one more time. And then it booted, listing some CMOS corruption error. Not sure how it uncorrupted itself magically this one time enough to tell me it was corrupted.

 

[waylo]

Never mind. Symptoms recurred and the whole computer went to heck.

Turns out it was the mobo, maybe the memory controller.

Replaced the mobo with something similar, kept the same memory and other hardware, seems to be up and running.