X670E PG Lightning no POST on cold boot

Just wanted to chip in and say that I got the same issue after updating the BIOS to 3.40 (and also 3.50) with cold boot. Downgrading to 3.30 solves the issue.

Had the same issue back in the day with my ASRock Z170 OC Formula after cold boot, never solved it (even changed CPU, RAM, Power Supply and GPU without success) and got myself another board (different brand), worked plenty of years without any troubles with the new board.

I don't see the point in changing my hardware when the problem is -as it seems- BIOS related. My components are brand new, working flawlessly with 3.30. The issue is the BIOS or some setting (related to the newer BIOS versions) which I coulnd't figure out yet.

The problem only occurs to me when shutting the pc down and cutting the power completely (removing power cord/switch the power strip off), but if I just shutdown the PC and restart it the next day/hours later without cutting the power, it boots fine (no such issue with 3.30).
It also doesnt matter if I leave the RAM at default settings (=not EXPO/OC related in my opinion), PC won't boot after cutting the power.

Unfortunately the new BIOS 3.50 continues this bug from BIOS 3.40. Back to BIOS 3.30 and no issues.

BTW, I use a power strip with a switch thus if I switch the power on that strip and press the power button at the PC it always starts without issues since the last 2 years but only with BIOS versions older than 3.40. With the versions 3.40 and 3.50 it will never start.

I replied in another topic but might do it here as well.

tl;dr cold boot doesn't POST, tried various fixes, finally changed to different RAM kit and it works fine now

Hi,

in this case it has nothing to do with the EXPO setting and also if it's set to 6000 MT/s or even higher. The issue is that after unplugging the power supply only the BIOS 3.40 can't boot the PC anymore.
So if you e.g. lower the RAM frequency and it starts thereafter then that indicates that either not all relevant BIOS settings for a successful boot process are stored in the CMOS correctly or that the stored values are incorrectly evaluated during the boot process after a power outage.
If I use BIOS 3.30, 3.25, 3.20 and even older ones this issue doesn't exist at all. The RAM runs even with EXPO 6200 MT/s, CL28, FCLK 2200, UCLK=MEMCLK, and VSOC 1.225V stable as a rock.
So long story short, if all other BIOS versions don't have this issue except the 3.40 then it's clear that there is a bug in BIOS 3.40.

Hi,

my system is also affected by this bug in the BIOS 3.40.
Reverting to an older BIOS like 3.30, 3.25, 3.20, etc. will immediately resolve this cold boot issue, which only occurs after unplugging the PC from the power supply.

CPU: 7900X3d
RAM: Corsair Vengeance 64GB Kit CMK64GX5M2B6000Z30 @ 6000 MHz and activated EXPO

I reverted back to BIOS 3.30 as long as this bug in 3.40 or a newer one is not fixed.