Thank you for the quick respond.
Right, so I have a BIOS flash back drive, I use it only for BIOS flash. It is FAT32 formatted, nothing has changed. BIOS file renamed, as stated. When I try the flashback, I receive a message. "Selected file not a proper BIOS!" I have saved all of the previous BIOSes for the mobo, so there cannot be problem with the BIOS files. I have tried to use the BIOS flashback button, it does no do anything, I am sure for the same reason.
I use TeamGroup T-Force Xtreem ARGB black, DDR4-3600, CL14 - 32 GB dual kit(B-Die ICs) and also a 5950X is installed into the mobo. For stability test, I have used Memtest86+ from bootable pendrive, also I tried Y-Cruncher and Prime95 for CPU stability test, and TM5 for memory test under Windows. I do encoding, around 6 hours per day, and there is no issue at all with DOC mod feature enabled.
By the way, there is no overclock in normal use, like games and idle state, only the memory XMP had been activated. I switched off the PBO, only the PB is enabled. I receive BSOD, random freezes, restarts, and black screen(00 or FF POST Code error) in idle status only. In games, everything is fine, under encoding, all good, all of the stability tests are running well for ages without error.
With BIOS version 3003 or the older 2601 everything was fine, I could push the memory beyond 4000MHz, if I wanted, but on 3800MHz with 1900 IF it was rock stable. There were two BETA BIOS also, those were stable too, but for memory OC, It needed more SOC and VDDG voltage.
It was stable before, also I had an MSI Tomahawk mobo until I received the Dark Hero, I use the same setup I used there. This madness started with the 3204 version BIOS. And I cannot understand, how it is possible, that under heavy load, there is no issue, after I leave the machine idle, and when I come back after half on hour, it has restarted, switched off, etc... On this morning, I could not make a successful boot for 15 mins. I needed to Clear the CMOS. After I loaded my saved profile, and everything was good again.
No it is working since 6AM under AVX intense encoding, it does fine. But I bet, when I finish, and I start surfing on the internet, or just leave the machine as it is in idle, I will get a random issue again.
It is possible, with the new AGESA microcode came off, that my CPU has hardware issue, as it happened the first line of AMD CPUs. I am also thinking to write to the AMD support, and I will ask RMA.