Unable to Post (qcode 42 > 62)

[rgb-cmyk]

Hi everyone,

My built my PC in November 2022 with EXPO and AMD overclocking enabled and it has been running without issue since then. For an unknown reason, the PC was unable to post this morning after completing a restart. The Q-code was 42. I tried clearing CMOS to no effect. I then used the flashback tool to update to the latest BIOS which succeeded, but is now resulting in Q-code 62 (with white LED). According to the manual this is "Installation of the PCH Runtime Services". I have left it in this state for the past 30 minutes to no effect.

Any recommendations on how to proceed?

CPU: AMD 7950X
GPU: MSI SUPRIM LIQUID X 4090
MOBO: ROG CROSSHAIR X670E EXTREME
RAM: G.Skill Trident Z5 Neo 32 GB (2x16) DDR5 6000 CL36

[rgb-cmyk]

Update: I tried removing the GPU to no effect. I have also tried going down to one ram stick and swapping the sticks in the recommended slots to no effect. Currently going slot by slot with one stick with up to an hour between for memory training. Getting C5 error.