X570 AORUS MASTER - won't post with BIOS past F22 (rev.1.2)

[Mirenia]

Hi everyone,

I've got a strange issue with a X570 AORUS MASTER Rev. 1.2 motherboard. The owner (my cousin in law) told me that over time he got more and more bluescreens until the board won't boot/post anymore.
It showed only post codes "C8, C3" and won't boot

I found a few things:
- cpu was faulty/dead (For further tests I replaced it with my own ryzen 7 3700X)
- with new cpu motherboard only runs on BIOS version F22 and below
-> And windows only runs stable if I set PCIe in BIOS settings to Gen 3. On automatic settings I got random bluescreens and USB ports and onboard LAN/WLAN won't work (showed power failure error in windows device manager)
- with BIOS F30 and above the "C8, C3" post code issue returns (flashing with Q-flash plus)


What could be responsible for this behavior?


Main power rail voltages are fine.
The only thing what got my attention was a very low resistance on PM_1VSOC/PCHIO (only 3 Ohms, but reading of 1V was fine and stable) -> comes from Chipset/PCH side
But I don't know if this is too low or not?

I also tried different CPUs and memory/RAM, another power supply and different graphic cards

[DynaxSC]

Probably chipset is degraded, I think 3 ohms is quite low. Don't have much experience with AMD chipsets, but comparing to Intel, 1V power line has min. 25-60 ohms. Further AMD chipsets are much more simple compared to Intel, so theoretically should be much less power hungry and have higher resistances on power supply lines.

The fact that the power voltage is stable says nothing, as the vrms used for chipset power supply usually are an "overkill" and can handle a few Amps current, so 3 ohms is no issue for them (3 ohms mean only 0,33A current at 1V voltage).

The good thing on AMD chipsets is they are much cheaper then Intel chipsets, and the BGA replacement is much easier, as the solder ball grid is quite less condensed then on Intel. The replacement is quite easy and almost always succesful, contrary to Intel which is a pain.

To go sure you might also try to reprogram the BIOS chip with a hardware programmer by hard using a stock image. Sometimes the BIOS image gets corrupted in areas which are not reprogrammed during normal BIOS or Flashback upgrade. Remember to do a backup of the old BIOS, as it might contain some individual motherboard data, like board serial, UUID, MAC Address, etc. which afterwards should be manually transferred to a stock, non-personalized BIOS image (DMI data).