[B650M PG Riptide] Bios not start, no hdmi output

Asrock B650M PG Riptide
Ryzen 5 7600x
2 x 16GB Corsair DDR5 5200 CMK5X16G1B52C40A2
AMD IGPU --> hdmi monitor 1920x1200

The kit was assembled in November 2022.
Integrated graphics have always been used - without a discrete graphics card. The memory strips worked in the default 4800 mode. And they were initially inserted according to the instructions.
There was never any overclocking.

After a year and a half of operation, the motherboard stopped displaying images via HDMI to the monitor (not even the BIOS is displayed). One morning, the computer simply did not turn on in normal mode.

When connecting a monitor via DisplayPort, the system most often does not start. It does not pass the memory check performed at system startup. The CPU and DRAM LEDs are on (even if you wait a long time).
Sometimes it starts and in this case, if you run furmark + cpu burn or a three-hour memtest (4800 MHz), everything works, it does not find any errors.
At the same time, without a load on the processor - over a long period of use, the system is extremely unstable. The screen blinks or the computer spontaneously reboots.
If you reboot the computer - it may not start, sometimes it starts on the tenth attempt.
Sometimes even the initial test passes, but at the moment the Windows login screen is displayed, a reset occurs.

If at the first start you manually reduce the memory to a minimum of 3200 with timings of 40-40-40-77-117, then the system works more or less stably.

At the same time, if you change any other parameter in the BIOS and exit with saving, then the next time the system most likely will not start (even the BIOS does not start)

Neither resetting or flashing the BIOS, nor replacing the power supply, nor pulling out any of the memory strips, nor reinstalling the processor and cooling system helps.
The situation does not change.
When installing discrete graphics - it starts more often, but still does not work stably.
The symptoms are very similar to this thread https://forum.asrock.com/forum_posts.asp?TID=25520&PN=2&title=b650m-pg-riptideno-post-after-reset-on-new-bios
But nothing indicated there helps.

The most important symptoms:
1. Complete lack of signal via HDMI (previously worked for more than a year).
2. Starts up and works stably only at the minimum frequency of DDR5 3200. At the same time, even at a frequency of 4800, the memory passes three-hour tests without detecting errors.

I suspect that the motherboard, processor, or both at once have died.

K9PT wrote: Asrock release a new Bios, did you check?!

1.11.AS03 - on this version of bios it worked for more than a year

When the described problems with launching arose, I tried in this order:
3.01 -> 1.21 -> 3.06
Newer versions have not been published yet.