I am calling upon the wisdom of my fellow AMD users with this post because I am all out of ideas at this point. Sorry if the post is somewhat lenghty I will try to add a TLDR at the end.
I have purchased the RX 6800 stock version from Sapphire a few months ago when it came out and so far I didnt have too much trouble with it until now.
When playing certain DX 11 it seems like I get unexplained crashes. The 2 games where I realized this are ARK survival evolved where I get crashes (total blackscreens only ended by switching psu power on and off) after 30-60 minutes and also in BF4 where I get crashes due to DirectX error after also 30-60 minutes. Havent had much trouble with other games so far. I am able to run furmark or timespy extreme while overclocking without any crashes for comparison.
I have been able to somewhat temporarily fix it by only installing the driver through windows driver tool after using DDU and not using the official AMD download. Ever since that I havent had any of these crashes However this way I cant use relive or any of the other software features like freesync that come with adrenaline which I really liked.
My 2 guesses are that either the card has power spikes (read several posts on reddit and amd forum about RDNA2 power spikes) that somehow exceed my 850 watt power supply or cause overvoltage protection to kick in or the adrenaline software doesnt work properly (apparently common problem on RDNA1)
Heres what I tried so far:
Formatting my pc and reinstalling windows
Reinstalling Adrenaline and AMD drivers with DDU several times
Undervolting the card in case it was having power spikes
using older drivers before 21.4.1 and 21.5.2
using the driver install option from windows which seems to have fixed it but leaves me without any of the amd software
My specs are this:
Ryzen 9 5900x
RX 6800 Sapphire stock edition
32gb 3600mhz trident z neo
1tb Samsung 980 Pro with the OS on it
2tb Crucial mx500 with the games in question on it
850w bequiet straight power 11 gold (this is a multirail psu for info)
x570 gigabyte aorus master mainboard
tldr: crashes in games when adrenaline software is installed but not when I only install the display driver
I have a Red Dragon 6800 and mainly fly in MSFS in VR. I have what sounds like the same issue and have done pretty much all of what you have done with no change at all.
I am very interested in your use of just the drivers eliminating the crashes.
When you do this can you still overclock and undervolt the card? Do you use other software to do it or do you just leave it stock.
The big puzzle for me is that the game runs perfectly for some time and then crashes. It does not give any hint that there is a problem.
I will have to give just the drivers a go and see how that goes for me and I will follow this thread with great interest.
I've tried just loading the driver and MSI Afterburner. My crashes still happen so my problem is different to yours.
I did have crashes when I first got the card that I fixed by installing an 850w psu in place of my old 750w.
In MSFS a lot of people with AMD cards are having trouble in VR and I do wonder if power spikes could be one cause. I have undervolted my card to 940mv and the crashes stay the same.
I have now attempted to connect 1x8 pin to one rail and another 8 pin to a different one and I also switched from a pigtail cable that has 2 8 pin on it to 2 standalone ones and the crashes are still there. I even get crashes now with only the display driver installed. Much less crashing but still often enough that its really annoying.
You say that this only seems to happen in dx11 games. MSFS is only dx11 at the moment but will supposedly go to dx 12 in a month so maybe my problems will disappear then.
I think my 6800 is very power hungry. It would not run on the same psu that i had been running a 2070 on. It would crash the system as soon as I turned on VR in MSFS.
Since i installed the new 850w psu I haven't had any troubles like that but I have constant ctd in MSFS.
Unfortunately I was unable to fix these issues. I have changed my RX 6800 out for a 3080 and now all is well again so far. If it turns out to be a different issue I will report back so others can benefit perhaps.