I reput my hardware section message because the problem can be due to driver .
There is always the bug with 7900 XTX with my 2nd 1080p monitor .7900 XTX display on this 2nd monitor in half in vertical , so in 540 x 1920 whatever connection wires ( DP or hdmi on my 1st or 2 nd monitor ) .
Said that, recently I had my PC crash when i was in game , sudden supply cut and must to unplug and replug the wire to restart my PC . Usually , when my computer crashes , it is due to DDR4 parameters but with DDR defaults parameters it crashed again .
When i return to desktop windows there is the message as " wattman default restored due to an unexpected error " .
That occured several times so much so that i opened my tower and see that the 7900 XTX was hot and the chipset heater was hot too .
What i didnt pay attention, is that i put the 2nd monitor to the 7900 XTX despite the bug of display .
I am not sure of that but i think that 2 monitors makes wattman bugging and makes 7900 XTX crash when in game , increasing too high the supply power .
After that i observed the 7900 XTX and saw that the 3 fans suxx the air by the top and put it in 7900 heater SO it is important that you PC tower has good fans that eject the hot air out of the tower , put in 7900 heater line if possible . Of course a good flow of air entering and exiting , always in line of the 7900 heater is better . It is obvious but that depends on tower configuration .
Before i looked that , i had the air entered by fans instead of ejected . The gain in game is that junction T° lowers from 90 °C to 82°C in average
Remark : we can see where the air goes from a fan seeing the hollow or not side of the fan . If it is at the hollow side , the air is ejected , aspired in other side .
The cause of crash is most likely not double monitoring while gaming because today it crashed even with 1 monitor 4K and at start of PC , so GPU and chipset were cold .
I removed X570 chipset driver but it crashed . ( I have now X570S motherboard )
I opened adrenalin and put GPU settings at undervoltage and GPU in games didnt crash .
So i think the cause is software , becoming from driver . Hope AMD launch decent drivers soon .
For the crash at cold , at start of the computer : ( 23.2.1 )
I changed my motherboard, migrating to X570S ( recently not today, days ago ). I didnt see that despite 4G enabled in Bios , Smart access memory was shut in adrenalin . I found on this forum i had to disable CSM in Bios .
So it looks like it works in game with default GPU parameters instead of undervoltage . Stay to confirm tomorrow when the PC will be all cold .
For the 2nd 1080p screen displayed in half vertical bug : ( 23.2.1 )
I tried today in windows, 3D parameters on and the bug disappeared but image isnt sharp, like 800 x 600 , dull colors , but in 1080p and staying at 30 Hz instead of 60 Hz .