No, I stayed with the 7900XTX, because the improvement with the Pico 4 is noticeable, and since it’s launch is my primary HMD also because Pimax didn’t support OVRMC.
I hope that Pimax address this issue with AMD for the current gen and also for the Crystal.
I tried the lastest AMD Drivers for the 7900XTX, and the behaviour is similar.
Now when I connect the 8KX with the PiClient open, I get a driver crash and a Diagonse of 10620 and then 20300. One time I get the 8KX tracked, but not working properly (I tried to open the Device Settings to put it in 90Hz, and the app hang).
This afternoon I’ll try with a PiTool version, but I don’t have high hopes in it.
I really hope that AMD give some new cards to @PimaxQuorra, @PimaxUSA and to the Pimax team and help them to solve this issue.
Just stumbled across this thread:
I tried a 7900 XTX for my 8K-X, too, coming from a RTX 3080.
=> Doesn’t work either:
Is connected and recognized without problems.
But as soon as starting ATS/ETS2 via OpenXR or simply the black grid room of SteamVR, I get horrible stutter and FPS below 20… Not playable at all.
As already stated in another thread here, AMD already admitted problems in VR in their latest driver 22.12.2 release notes.
So hopefully, they can fix this issue.
If the 7900 XTX then will perform good enough and even better than a RTX 4080, well, remains open…
I got mine working (kinda), actually:
7900 xtx, 12-2 radeon software, 2.1.255.299 firmware, 1.0.1.284 pitool
To get it running I had to kill and restart pitool a couple times but eventually it stabilized and was running. The problem though, is that once it was running, it would show tracking and connectivity to lighthouses, but the screen was either dead black screen, or sometimes careening/spinning wildly… Which from this thread, it sounds like where everyone is getting stuck.
For me, whether black screen or spin, I could then turn off lighthouse mode, and suddenly have perfectly clear video. On 9-axis mode, video works brilliantly… Too bad 9axis mode is vomit inducing and functionally unusable.
But to me, I have to wonder why the lighthouse/head tracking has anything at all to do with the video card or drivers
– and since I’m not coming up with a good answer to that, whether this has anything to do with drivers at all.
Probably the crashes, and we’ve seen that VR performance on other headsets is not any better than last gen, which AMD has admitted. But no other headsets are this completely non-functional. Performance, blame on AMD. But basic functionality? C’mon pimax, this is on you.
Sorry, wrong.
=> Just google for “7900 xtx vr issue” and have fun reading through all the non-Pimax related threads and posts on Reddit, i.e. 
i.e. this one clearly states that is “only” driver issues, and especially and apparently “only” on the Windows side:
https://www.reddit.com/r/Amd/comments/zwyton/proof_7900xtx_vr_issues_are_due_to_a_driver/
Linux seems to work fine - even though the performance isn’t that overwhelming compared to a RTX 4080.
And the problem has been admitted by AMD in this topic, too, as you’ve written yourself:
But it is affecting many many VR headsets from all manufacturers, if you read closely, and when it comes to such a stuttering and FPS <20, I, from my point of view, would consider this as “completely non-functional” - almost eight years after DK2
It is not that Pimax shouldn’t have a closer look, too, for sure, and especially discuss this with AMD.
But imho, first AMD must repair the general broken VR functionality before any headset manufacturer such as Pimax can investigate on further issues on their side.
The workaround for black screen in the headset is to use onboard graphics for your pancake display therefore seperating the two displays with different refresh rates. An oooold AMD driver bug that still plagues the Radeon drivers. Still working on the wildly spinning headset display issue. Not really making any headway on this one as far as workarounds go. Anyone found a way yet?
Tested latest Radeon Drivers 23.1.1 and the behaviour is the same, driver crash when the Pimax Driver tries to “talk” to the headset.
With the Pimax Client after the carsh an error 10620 is marked but quickly changed to error 20300 (and in the HMD the led is Red). If I stay in that way with the HMD connected, the Pimax drivers tries to talk with it again and get another Driver crash.
With the PiTool 275, after the crash que program freezes, so I couln’t see any error.
@PimaxQuorra I wanted to know if there is a way to change the HMD config without the PiTool/Pimax Client, maybe with a Firmware restore or something. Because when I have it at 90Hz native, at least I got a spinning image in the HMD and no driver crash.
EDIT: I reflashed the FW M299 (the same it had), and the crashes still there, so maybe this didn’t restore the default configuration, or the crash problem affects to the default configuration as well.
EDIT 2: I mounted the 6800XT in the PC, and with it the 8KX is working fine, but the configuration didn’t restore with the FW Flashing, because the HMD was in 75Hz (instead of 60) when I conected it to the PC.
Hello,
Unfortunately, the HMD could not be configured without the Pitool/Pimax Client.
I would recommend filing a ticket with our tech specialist so that they can arrange a remote session and thoroughly troubleshoot your setup and headset.
In the meantime, I will notify our engineers, who may be able to propose an appropriate solution.
Thanks for the reply 
But after think about it, I returned the 7900XTX and I’ll go for a 4080/4090, which have less problems in VR (and also compatibility with DFR).
Meantime the 6800XT is performing well in the vast majority of games.
Hello,
Indeed, I’ve seen quite a few reports that the 7900 isn’t functioning well in “VR,” not only with Pimax but with other VR-related apps.
Meanwhile, we’re working with AMD to resolve certain compatibility issues.
I hope the 40 series is going well for you!
AMD themselves have acknowledged VR performance with the 7900 XT/XTX as a “bug” that they are actively working to fix. No one, with any headset, should be getting one of these cards right now.
My 5k Super isn’t working either. When I first plugged it in I was able to get it to display the Pimax home environment but at about 3fps. Video here → https://cdn.discordapp.com/attachments/376051993518800926/1053430686792548392/VID_20221216_215613.mp4
Since then it now just crashes whenever I turn on the headset with Pitool open. Very annoying and very concerning.
AMD have said that VR is broken on the new cards. Not pimax specific afaik.
At least the other headsets work though.
That’s not true. There is a known issue in the drivers that SOME games doesn’t have the performance it should, but with other games it works fine.
I used it with a Pico 4 + VD in godlike, and in MSFS 2020 the improve from a 6800XT is near 40%, in other 30% (ACC) and in other 10% or less (No Man’s Sky).
And they also work with other HMDs, so the cards work for VR, is not broken as you claim.
Thanks for that! Glad to hear it’s not as widespread as I thought.
I thought the Pico 4 is not connected to the display port of the graphics card?
Those are completely different conditions.
Didn’t Kevin also say at some point that DP2 had problems with cable lengths over 2-3 meters?
Maybe also something to test with an extender. 
Yes, it’s not connected to the GPU, the data is sent encoded over wifi or USB (in my case over wifi with Virtual Desktop), but the VR Known Issue in the drivers affect this as well.
The Pimax problem is probably also driver related ( I think 50/50, because other cable HMD are warning), but is not the known Issue of the drivers release.
Confirmed VR fix for my system was to install MSI center and no need for uninstalling/reinstalling MSI center either as VR just works now. The only issue I still have is the tracking jitter/lag but that appears to be a pimax tracking issue for 9 axis tracking as that is all I use so I can’t comment on lighthouse tracking functionality. The rapidly spinning display and poor performance is completely gone and VR performance is really very good. My system specs are as follows. MSI X670 Pro motherboard 7700X cpu 32 Gigs G Skill 6000 memory XFX 7900XT and cheapo 1 TB ssd non nvme as the system is still on the test bench. Pimax 5K super HMD. Credit for this fix goes to JonnyM from this thread Can We Get Acknowledgement of the Pimax Specific RTX 4090 Latency / Lag Issue please? - #461 by DustyBritches
@elin77: You cited individuals having specific issues, but fact: Every single other major VR headset model with the 7900XTX works in most games, and works well (at least as well as last gen) in most games - Except Pimax. (Note: this was supposed to say "works in most, works well in many, but I wrote most both times which is less true)
Another fact: At least a few of us have even got Pimax working - by changing around pimax software versions, and disabling lighthouse tracking - Neither of those changes helping the issue seems supportive of AMD drivers being the root cause.
No number of anecdotes is an effective counterargument to facts.
Neither of us have access to the code here, but the information we can see says the root cause is on Pimax’ side - and if that’s the case (as it appears), waiting for an AMD driver fix isn’t going to help.