Guys,

Thanks for the responses. I'm going to give those schematics a view tomorrow and see what I find.

Much appreciated,
Brandon

ciornyi wrote on 2022-09-05, 17:27:

Hey mate, Id recommend you to use Board view programm . There is alot board view files for p4c800 any revision . ill try to att […]
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Hey mate,
Id recommend you to use Board view programm . There is alot board view files for p4c800 any revision . ill try to attach those files here. This programm will show every component and where it goes and to what connected

ps rev 2.0 is much weaker coz has less components left so it migh be less stable in overclocking . Pre 2.0 revision has more caps at cpu power line.
pss programm itself you can easy find in internet
Psss i think that your bios simply corrupted

I honestly can't find any hardware faults at this time and agree with you. Is there any component of the BIOS aside from the BIOS chip itself that I can inspect? I've replaced the physical chip twice to no avail.

There's a second "chip" that has 8 legs that plugs into the motherboard just below the actual BIOS chip? What the hell is that thing? I can't find a description of it anywhere?]

I know this picture is from a P4P, but it's the same type of component on the P4C

cactusjuice wrote on 2022-09-06, 00:46:

***
There's a second "chip" that has 8 legs that plugs into the motherboard just below the actual BIOS chip? What the hell is that thing? I can't find a description of it anywhere?]
***

It's connected to W83791SD -

W83791SD is a programmable speech synthesizer with 9-bit current DAC output that can connect to speaker or LINE_OUT by the AC’97 […]
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W83791SD is a programmable speech synthesizer with 9-bit current DAC output that can connect
to speaker or LINE_OUT by the AC’97 audio codec.
...
The W83791SD/SG could connect W55FXX to store voice data

The purpose of the chip W83791SD should be something like that:

For example: As BIOS usually has POST (Power On Self Test) program, then it will test every item step by step if no failure take […]
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For example: As BIOS usually has POST (Power On Self Test) program, then it will test every item step
by step if no failure takes place, however, if it detects a failure on a specific item, it will hang on there.
Therefore, BIOS could write timeout value to register 08h and start timer setup speech trigger event
(register 09h), then BIOS test program starts. Whenever the system is hang on specific item such as
DRAM testing, W83791SD/SG would say “DRAM test fails” after the timeout previously set at CR [08h].
On the contrary, if DRAM test is ok, then BIOS could update the timeout value and proceed to the next
test program.

P.S. An addition about the MCH power signals.
Q187 (there is no such mosfet but there's footprint) pin 3 - should be voltage equal Vcore of CPU as it's going through an inductor L99. It's MCH VTT power rail.

P.P.S.
Maybe can be useful (I don't know):
ASUS Mother Board Elementary Troubleshooting Guide