Basic Setup – OpenXR & Pimax HMDs...

[everest101]

I have been testing my VR configuration/stability & visual improvements with my Pimax5k Super HMD since DCS provided OpenXR support. At first, tests where KO and could hardly just get to the flight phase. But a recent break through has occurred and has changed the testing results by 180 degrees for the better.

The big game changer happened yesterday when I found out that the OpenXR Toolkit was revised to v1.2.4. to improve usability with DCS OpenXR implementation, see note 1.

I will spare you the testing details and jump directly to some results/configurations that work for me.

Hardware configuration:  (if you wish to compare, here are my PC details)

Mobo:              MSI X570-A PRO/PCIe 4

CPU:               AMD RYZEN 9 3900X (12 CORE)

GPU:               EVGA-RTX 3080Ti

RAM:              DDR4-32 GB (3200MHZ wt XMP)

HMD:              PIMAX-5K SUPER

Software configuration:

DCS World Open Beta v 2.8.2.35759 (latest as of 3 FEB 2023 & wt OpenXR support)

PiTool v1.0.1.284v - Version 284 is required as per PimaxXR requirements. See note 1.

PimaxXR v0.3.0 - This app is the runtime required for OpenXR to work with PiTool and to bypass SteamVR. PimaxXR runtime is needed to avoid PiTool kick starting SteamVR by default. Install PimaxXR and make sure that PimaxXR is selected as the OpenXR runtime. See note 2.

OpenXR Toolkit v1.2.4 – Latest version as of 2 FEB 2023.  See note 3.

OpenXR Explorer v1.4 - Optional application to analyze OpenXR runtimes & OpenXR Toolkit app that is installed. Not required for success in implementing OpenXR with DCS. See note 4.

OpenComposite - This application and its DLL implementation into DCS is not required for success in implementing OpenXR with DCS. However, you may need it for other VR games or simulators that are designed to use the SteamVR app to run them in VR. See note 6.     

Recommendations:

• Always make sure that the PiTool app is UP and running regardless of what VR runtime (SteamVR or OpenXR) you use. Otherwise, your Pimax HMD is not available for your VR sessions.
• If you have configured a DCS game start icon in PiTool and wish to test OpenXR runtime, avoid using that game start icon. Starting DCS from the PiTool/My games/DCS icon will kick start SteamVR. Having DCS started via SteamVR while OpenXR is configure for the game will likely cause undesired results. If you are going to run or test DCS OpenXR VR method (bypassing SteamVR), for safety, just delete the game start icon in PiTool as you will not really need it anymore. Instead, do the following…
• Exploit the DCS command line features to start the simulator as these will be useful to you. Make yourself some DCS game start window shortcuts to facilitate things. Here are some windows shortcut command line targets that I use. Make a DCS game start shortcut for each of the following shortcut targets & see note 5 for other DCS post link;  

"your game install path\DCS World OpenBeta\bin\DCS.exe" --force_enable_VR --force_OpenXR - to start DCS with OpenXR support. Make sure that SteamVR is not running. Make sure that OpenXR Toolkit is enabled. At first, use the default Toolkit shortcuts. Also, make sure that active OpenXR runtime is ticked back to OpenXR within the PimaxXR app. This will enable bypassing SteamVR and will avoid SteamVR from being called.

"your game install path\DCS World OpenBeta\bin\DCS.exe" --force_enable_VR --force_SteamVR - to start DCS with SteamVR support. If you revert back to using SteamVR, make sure that the OpenXR Toolkit is disabled (tick the disable switch in OpenXR Toolkit) and that active OpenXR runtime is ticked back to STEAMVR within the PimaxXR app (start PimaxXR app and select SteamVR as the runtime).

"your game install path\DCS World OpenBeta\bin\DCS.exe" --force_disable_VR – to start DCS without VR so that DCS displays on your primary display screen. This could useful for HOTAS configuration, etc.

• Without guaranties, this methodology should work for Pimax4k, 5k or 8k HMD owners.
• Can all these pieces of software & apps co-exist at the same time on your PC. YES, however, configuring the apps correctly is required if you wish to use DCS with SteamVR or with OpenXR. See comments above depending on the shortcut command lines that you are using to start the DCS simulator.
• You need to experiment with the OpenXR Toolkit settings. Do that using the Toolkit shortcuts while in the game. Settings will likely vary if you have a Pimax4k, 5k or 8k HMD.

When your satisfied with your Toolkit settings, share them with the community by writing your own post.

Using OpenXR...

Generally speaking, I am getting better control of my FPS frame rates, better control of color effects and better control of sharpness inside the cockpits.

Since using PimaxXR v0.3.1, stuttering when switching from F1 to F10 and back to F1 views has disappeared.

Use OpenXR Toolkit to experiment with OpenXR setting while in the simulator. Use default OpenXR Toolkit shortcut combos to facilitate your setups.

So far, multiplayer seems OK.

Hope this helps you enjoy OpenXR with your Pimax HMD.

Everest…Out!

Notes:

1-      For PiTool v1.0.1.284v, see https://community.openmr.com/t/pitool-1-0-1-284v/39823 Version 284v is not available for download from Pimax Support site. select the supplied link to Pimax's OpenMR community to get PiTool v1.0.1.284v. 

2-      For PimaxXR v0.3.0, see https://github.com/mbucchia/Pimax-OpenXR A new (unreleased as of 8 FEB 2023) version of PimaxXR is available, V0.3.1. See the following forum post to download a pre-release version of PimaxXR v0.3.1. GO TO FORUM POST LINK

3-      For OpenXR Toolkit v1.2.4., see https://mbucchia.github.io/OpenXR-Toolkit/

4-      For OpenXR Explorer v1.4, see https://github.com/maluoi/openxr-explorer/releases/tag/v1.4 Be aware that this app is not required for OpenXR implementation with DCS. It is included here as reference only and is recommended for folks that do application development work.

5-      For DCS news letter regarding OpenXR implementation, see the following forum post: https://forum.dcs.world/topic/318004-dcs-now-supports-openxr-natively/

6-      For OpenComposite & OpenComposite switcher, see https://mbucchia.github.io/OpenXR-Toolkit/opencomposite.html Note that no revision is mentioned for OpenComposite probably because this is actually a DLL which did the work of throwing DCS VR runtimes to PimaxXR before introduction/support of OpenXR in DCS. OpenComposite solution is no longer required to operate OpenXR in DCS.  

[Montrose]

Okay this is great but how to you apply all your game title specific settings for color, rendering etc that is set using pitools if you don't launch the title form piTools? There is a lot of tweaking done in the PiTools app to make things look good.

[WipeUout]

Great post @everest101, thanks for starting this.

I have not tried with my 5k Super but will do eventually.

As for my 8kX, the native OpenXR DCS support is providing even more performance compared to using opencomposite.  I have gained 1ms in GPU frametime and 1.3ms in CPU frametime with my test track in Caucasus with the f-18.

I set pitool at native resolution, 60hz, normal FOV with a bit of backlit increase.  No compulsive smoothing whatsoever and no fix foveated rendering as it does not work in DCS from pitool.

In OXRTK I use fix foveated rendering at 55/80/100 and the performance gain is really good.  The Pimax HMD is the ideal VR headset to use fix foveated rendering because of the large FOV, but personal preferences may vary.  I use also CAS sharpening at 80%, no modification of the resolution.  4k native is very nice and clear, I do not use MSAA anymore as the higher resolution is the best cure for aliasing.  If you have the newer 8kX with 90 hz minimum refresh rate, you might still need some compulsive smoothing or to scale down some settings.

 

[WipeUout]

2 hours ago, Montrose said:

Okay this is great but how to you apply all your game title specific settings for color, rendering etc that is set using pitools if you don't launch the title form piTools? There is a lot of tweaking done in the PiTools app to make things look good.

Have you tried importing the DCS.exe from your game list?  If imported, it will become available in the game specific setting as "DCS" and you might be able to make it work that way.  I will give it a try and let you know if it works. 

[WipeUout]

1 hour ago, WipeUout said:

I will give it a try and let you know if it works. 

It's working fine.  Click import and point to DCS.exe, then go in your settings and you should see DCS in the game list.  when you start the game with the shortcut, Pitool will detect dccs.exe and apply whatever setting you defined specifically for it.

[everest101]

On 2/13/2023 at 11:53 AM, Montrose said:

Okay this is great but how to you apply all your game title specific settings for color, rendering etc that is set using pitools if you don't launch the title form piTools? There is a lot of tweaking done in the PiTools app to make things look good.

Hi @Montrose, 
Good question and you are right that if your game is not part of a game title in the PiTools / Game tab, then you cannot fire the game from PiTools and specific settings for that game via PiTools / Settings + Games option cannot be customized or used for that game....yet here is what I do and it does work fine....

Firstly, I do not import into PiTools / Games tab any specific game that I wish to bypass SteamVR. This includes both my DCS and MSFS2020 games that currently bypass SteamVR VR runtimes in favor of using OpenXR/PimaxXR VR runtimes. So, I no longer count on the PiTools/Settings + Game setups for either of these game titles. So how do I adjust VR settings for either of these games?

I do those setups using OpenXR Toolkit settings and I can do it for each game. I cannot explain how it is controlled and where it is stored but OpenXR Toolkit settings are stored for each game. It also appears that settings can be different for each game....but I have NO idea on how the OpenXR Toolkit does it. The important thing though is that it CAN be done! 

Also, in OpenXR Toolkit, you can fiddle with color settings with a lot more parameters (color contrast, luminosity, saturation, etc.) than in PiTools. You can control rendering resolutions, upscaling techniques, FOV parameters and so much more and tweak it on a per game basis. You get the hang of setting things up using the default CTRL F1, F2 and F3 shortcuts. It is worth it to try this out. 

I get better end results than using PiTools with SteamVR...for sure! And, as a bonus, my game FPSs are higher.  

While I am still experimenting, once I am done and happy settings up, I will post my OpenXR Toolkit setup result here.  

Hope that helps... 
 

On 2/13/2023 at 12:59 PM, WipeUout said:

Great post @everest101, thanks for starting this.

 

I have not tried with my 5k Super but will do eventually.

As for my 8kX, the native OpenXR DCS support is providing even more performance compared to using opencomposite.  I have gained 1ms in GPU frametime and 1.3ms in CPU frametime with my test track in Caucasus with the f-18.

I set pitool at native resolution, 60hz, normal FOV with a bit of backlit increase.  No compulsive smoothing whatsoever and no fix foveated rendering as it does not work in DCS from pitool.

In OXRTK I use fix foveated rendering at 55/80/100 and the performance gain is really good.  The Pimax HMD is the ideal VR headset to use fix foveated rendering because of the large FOV, but personal preferences may vary.  I use also CAS sharpening at 80%, no modification of the resolution.  4k native is very nice and clear, I do not use MSAA anymore as the higher resolution is the best cure for aliasing.  If you have the newer 8kX with 90 hz minimum refresh rate, you might still need some compulsive smoothing or to scale down some settings.

 

@WipeUout, thanks for sharing some of your setup results. 

Edited February 15, 2023 by everest101

[Rodeo]

So now with MT what is everyone trying with settings?

I have everything up and running but haven’t messed around with OXRT yet. 

[WipeUout]

Instable experience so far.  Not sure what is causing it but when using PimaxXR and OXRTK with the MT version, I get what looks like HMD tracking issue with image lag and wobbles as soon as I move my head.  This starts when I switch view from cockpit to map but not all the time.  The wobbles and lag goes away after a while but not always.  I haven't found what is causing this nor how to stop it.  This issue was also present in menus prior to the latest OB but not anymore since OB 2.8.3.38090.  I have to try OXRTK 1.3.0 to see if this will correct the issue, I am still using 1.2.4.

When my "tracking" problem is not happening, my performance is great with MT.  My CPU frame time dropped dramatically from 8.2ms down to 3.3ms.  On the GPU frame time, there is also a good drop from 12.9ms to 11.6ms.  This is GPU performance that is even better than what I had with DCS 2.7.18.  As a result, I can now use MSAA 2x and maintain 60 FPS and 100% native resolution in any situation including flying in Syria over Aleppo at 1000ft.  I'm using same settings in OXRTK with fixed foveated at 55/80/100 and nothing else.

In Pitool, I increased backlit and brightness to compensate my gamma setting in DCS.  I now use a DCS gamma setting of 1.3 which effectively reduce haze quite a bit but requires higher level of brightness/backlit.  I do not use smoothing or reprojection, nor fixed foveated in Pitool as it does not work.  

I keep same settings in DCS with clouds normal, flat shadow with blur off, no anisotropic filtering, vis. range ultra and now MSAA 2x.

[Nahemoth]

hace 2 horas, WipeUout dijo:

Instable experience so far.  Not sure what is causing it but when using PimaxXR and OXRTK with the MT version, I get what looks like HMD tracking issue with image lag and wobbles as soon as I move my head.  This starts when I switch view from cockpit to map but not all the time.  The wobbles and lag goes away after a while but not always.  I haven't found what is causing this nor how to stop it.  This issue was also present in menus prior to the latest OB but not anymore since OB 2.8.3.38090.  I have to try OXRTK 1.3.0 to see if this will correct the issue, I am still using 1.2.4.

When my "tracking" problem is not happening, my performance is great with MT.  My CPU frame time dropped dramatically from 8.2ms down to 3.3ms.  On the GPU frame time, there is also a good drop from 12.9ms to 11.6ms.  This is GPU performance that is even better than what I had with DCS 2.7.18.  As a result, I can now use MSAA 2x and maintain 60 FPS and 100% native resolution in any situation including flying in Syria over Aleppo at 1000ft.  I'm using same settings in OXRTK with fixed foveated at 55/80/100 and nothing else.

In Pitool, I increased backlit and brightness to compensate my gamma setting in DCS.  I now use a DCS gamma setting of 1.3 which effectively reduce haze quite a bit but requires higher level of brightness/backlit.  I do not use smoothing or reprojection, nor fixed foveated in Pitool as it does not work.  

I keep same settings in DCS with clouds normal, flat shadow with blur off, no anisotropic filtering, vis. range ultra and now MSAA 2x.

Yesterday I noticed this same effect after switching back from the map view. But after exiting the mission and entering again in another one, it recovered from the previous bad behaviour.

[Rodeo]

8 hours ago, WipeUout said:

Instable experience so far.  Not sure what is causing it but when using PimaxXR and OXRTK with the MT version, I get what looks like HMD tracking issue with image lag and wobbles as soon as I move my head.  This starts when I switch view from cockpit to map but not all the time.  The wobbles and lag goes away after a while but not always.  I haven't found what is causing this nor how to stop it.  This issue was also present in menus prior to the latest OB but not anymore since OB 2.8.3.38090.  I have to try OXRTK 1.3.0 to see if this will correct the issue, I am still using 1.2.4.

I am having the same exact issues as well. Figured it was something I was missing a setting or doing it wrong.   When things do “correct” itself it does seems much better on performance just like you are seeing. 
 

Thank 

Edited March 27, 2023 by Rodeo

[WipeUout]

15 hours ago, Rodeo said:

I am having the same exact issues as well

Sad but relieved to learn that it's not only me.

I have installed OXRTK 1.3.0 and it did not correct the issue, on the contrary I got back the wobble/lag in the menus again!  I can't rule out either PimaxXR or OXRTK for causing the issue, this is puzzling.  I'm thinking about rolling back to Pitool 1.0.1.281, since this is the stated "better" option for compatibility with PimaxXR 0.3.2 according to the wiki on github, and see what happens.

[m0zz]

I was having the same issue too. I read on the discord to cap the frame rate at 90 or whatever hertz you are running and to enable turbo mode in oxrtk. It runs rock solid for me now, no jitters.

[WipeUout]

1 hour ago, m0zz said:

I read on the discord to cap the frame rate at 90 or whatever hertz you are running and to enable turbo mode in oxrtk.

I just tried also and it solves the problem but not 100%.  Occasionally, the lag/wobbles will start but will not last very long, it will go away as soon as you start rolling the aircraft.

Another way around is to use PimaxXR 0.2.4 instead of the latest 0.3.2.  This will remove the lag/wobbles but may introduce some micro stutters which was what I experienced.  The previous workaround is better for me.

I used 61 FPS for frame rate throttling (since my HMD refresh rate is set to 60) along with turbo mode "ON".  I did notice a slight loss in performance of about 0.5ms increased GPU frame time though.  Not a huge problem.

@mbucchia (author of PimaxXR) commented on github that he will not able to get back to his PimaxXR project before May, we will have to be patient for a more elegant solution.

Edited March 27, 2023 by WipeUout
Typo

[Nahemoth]

And why not going back SteamVR? At least until these problems are solved...

[WipeUout]

17 hours ago, Nahemoth said:

And why not going back SteamVR? At least until these problems are solved...

You are right, this is another solution. But there are also issues with SteamVR.  Very glad you ask that question because it is not a bad option now!

First, when using the MT version, the Pitool Fixed Foveated Rendering (FFR) does not work.  FFR is a powerful feature that can improve performance significantly without sacrificing too much quality. With the wide FOV of the Pimax HMD, it is the ideal HMD to use with this feature.  Unfortunately I tried many times, including today, and it will not work with SteamVR.  On the other hand, it does work with the ST version which is new and welcomed as it lower GPU frametime considerably.  From my testing, I have found a 1.0ms reduction in GPU frametime.  This is using the balanced setting.  This feature in Pitool is as good as the one found in OXRTK giving very similar results in improved performance.

Second problem is the loss of sharpening with MT.  The CAS sharpening option in OXRTK was very useful as the default VR view in DCS is very blurry.  There are no sharpening options in SteamVR unfortunately but some mods can help.  I tried many re-shaders and none seems to work with MT.  On the positive side, I found that VRToolkit Reshade works perfectly with the ST version.  This is also very welcomed.  You just have to find the sweet spot as too much sharpening can make the FFR circles visible.

In all, the ST version using SteamVR is pretty good and on par with using ST with PimaxXR/OXRTK as far as performance.  I also noticed that SteamVR seems more stable with less random stutters.  I still need to do more testing but so far so good, this is what I will be using going forward until MT is fixed. 

[Nahemoth]

En 29/3/2023 a las 16:03, WipeUout dijo:

You are right, this is another solution. But there are also issues with SteamVR.  Very glad you ask that question because it is not a bad option now!

First, when using the MT version, the Pitool Fixed Foveated Rendering (FFR) does not work.  FFR is a powerful feature that can improve performance significantly without sacrificing too much quality. With the wide FOV of the Pimax HMD, it is the ideal HMD to use with this feature.  Unfortunately I tried many times, including today, and it will not work with SteamVR.  On the other hand, it does work with the ST version which is new and welcomed as it lower GPU frametime considerably.  From my testing, I have found a 1.0ms reduction in GPU frametime.  This is using the balanced setting.  This feature in Pitool is as good as the one found in OXRTK giving very similar results in improved performance.

Second problem is the loss of sharpening with MT.  The CAS sharpening option in OXRTK was very useful as the default VR view in DCS is very blurry.  There are no sharpening options in SteamVR unfortunately but some mods can help.  I tried many re-shaders and none seems to work with MT.  On the positive side, I found that VRToolkit Reshade works perfectly with the ST version.  This is also very welcomed.  You just have to find the sweet spot as too much sharpening can make the FFR circles visible.

In all, the ST version using SteamVR is pretty good and on par with using ST with PimaxXR/OXRTK as far as performance.  I also noticed that SteamVR seems more stable with less random stutters.  I still need to do more testing but so far so good, this is what I will be using going forward until MT is fixed. 

I think that I will stay in MT version with SteamVR, I will do some performance tests for comparing results.

[ackattacker]

I haven't had a lot of time to optimize it but I have OpenXR/PimaxXR/OpenXRTK working marvelously on my system with multithreading. Only thing is motion reproduction is a mess, but isn't needed with the proper settings. SteamVR works better with motion reproduction but is a much worse experience overall.

5800x3d/3080Ti/32GB/Pimax 8KX DMAS (2076)

Pitool V1.0.1.284

Headset firmware V2.1.255.2003 (this is the 120Hz beta firmware)

PimaxXR v0.3.2

OpenXR Toolkit v1.3.0

Pitool settings 75Hz, Normal FOV, Render Quality 1, FFR OFF, PP OFF, Smart Smoothing OFF, vertical sync OFF, Hidden Area Mask ON

DCS Settings VR Preset, PD 1.0

OpenXR toolkit settings Target Frame Rate 75, Upscaling NIS 80% sharpness 20% FFR Performance/Wide Turbo ON

Launch DCS-MT with --force_enable_VR --force_OpenXR

Initial testing the system maintains 75fps rock steady with about 10% GPU headroom. This is on single player missions, I have not yet tested multiplayer. The overall experience is smooth. I have no issues with jitters/microstutters/menus etc. It all works fine. Like I said this is not highly optimized settings, just settings that work as a starting point. If you have a 4090, I suspect 90fps is easy peasey probably without upscaling.

 

Edited April 5, 2023 by ackattacker

[WipeUout]

4 hours ago, ackattacker said:

If you have a 4090, I suspect 90fps is easy peasey probably without upscaling.

With the settings you mention probably yes, I can with my 4080.  But the real beauty with the 8kX is running at native resolution which gives a very detailed view and minimize shimmering to a tolerable level without resorting to MSAA.  Of course the view is even better with MSAA, almost perfect.  I keep my refresh rate at 60hz to avoid any upscaling and can even afford MSAA 2x without problem on busy multiplayer missions with plenty of headroom.  The 8kX at native resolution is really shinning.

[ackattacker]

1 hour ago, WipeUout said:

 I keep my refresh rate at 60hz to avoid any upscaling and can even afford MSAA 2x without problem on busy multiplayer missions with plenty of headroom.  The 8kX at native resolution is really shinning.

I tried 60Hz mode without upscaling and couldn't take it. 75Hz is minimum for me for an enjoyable experience, 90Hz is noticeably better. I will drop all other visual settings to achieve at least 75Hz. Everyone is different. I also cannot stand motion reprojection even when it's working properly. The double images drive me batty. The MT build is a literal game changer for me because previously I would be CPU limited trying to achieve steady 75fps on busy missions. Now that the CPU is not the limit I may have to sneak out and buy a 4090. This is an expensive hobby.

Edited April 5, 2023 by ackattacker

[ackattacker]

I did run out and get a 4090... now I can achieve 90FPS consistently at native resolution normal FOV (I am using still using FFR), high textures, medium shadows, no MSAA. Even busy multiplayer no problem. It looks and feels great, finally I feel the 8kx is living up to it's promises. 

[WipeUout]

Update!!

Wow, MP is now working very well with latest OB 2.8.4.  here is my recipe:

OXRTK 1.3.1

PimaxXR 0.3.4

Nvidia 531.61

Pimax Client 1.10

I am not seeing the same performance as before when it was wobbling like crazy in the menus but very close within 0.2 to 0.3 ms for GPU frametime.  Pimax client 1.10 is a must as with Pitool 1.0.1.284 the instabilities were still showing.

Even the 2 second repetitive micro-stutter is gone in MP!  Thanks ED and @mbucchia!!!

I still have to try a few things such as compare Fixed Foveated between OXRTK and Pimax to see which is more efficient.  Will get back with more update. 

UPDATE: Pimax FFR (still) does not work with OXR, on the other hand OXRTK FFR works well with 1.2ms drop in frametime, in my test track on performance preset. 

Edited April 16, 2023 by WipeUout
New info and findings

[WipeUout]

Here are my actual settings below.  I am having the best experience so far with the 8kX, very clear and smooth visuals for the vast majority of scenarios.

First the Pimax settings and then the DCS Setings.

As you can notice, I use 90hz which is the maximum refresh rate on my 8kX (older model).  The 75 or 60 hz is usable but a bit flickery in menus.  Using 75 or 60 hz allows higher settings though if you can sim at that rate.

At 90hz, you should be able to maintain at GPU frametime bellow 11ms most of the time with those setting but need at least a 4080.  The CPU is no longer a limiting factor with Multi-threading(MT).

For DCS settings, it is up to your personal taste but running the 8kX at native resolution, I find that MSAA is not required as the best cure for aliassing is higher resolution.  If I run the HMD at 60hz, then I have the horspower to use MSAA but the quality gain is not that much.  MSAA has a very high cost in terms of GPU frametime.  On average, I increase my GPU frametime by 2.7ms which is huge and would force me to use re-projection and this is a no-go for me.  Native resolution without reprojection is the objective! 

You may notice also that my gamma setting is pretty low and this is to reduce haze.  It is a good and efficient way but you have to crank up your backlit and brightness to compensate.  

As for windows stuff, I have HAGS on with not issues and leave nvidia driver 3d setting pretty much at default except power management set to max performance.  For other software such as Pimax client, PimaxXR and OXRTK versions, see my previous post.  Running these exact versions is the key to have a smooth DCS MT experience. 

Some additional info about OXRTK:  I do not overide the resolution but use Fix Foveated Rendering (FFR) at performance setting and CAS at 100%.

Note that the pimax client FFR does not work with DCS-MT and OpenXR. 

We all have different hardware setup and this is why it is so challenging to find that sweet spot but hope this can help.

 

[ackattacker]

I have been running very similar settings with my 4090 with good results. It is stable and smooth at 90fps. 

[Nahemoth]

En 10/5/2023 a las 16:43, WipeUout dijo:

Here are my actual settings below.  I am having the best experience so far with the 8kX, very clear and smooth visuals for the vast majority of scenarios.

First the Pimax settings and then the DCS Setings.

As you can notice, I use 90hz which is the maximum refresh rate on my 8kX (older model).  The 75 or 60 hz is usable but a bit flickery in menus.  Using 75 or 60 hz allows higher settings though if you can sim at that rate.

At 90hz, you should be able to maintain at GPU frametime bellow 11ms most of the time with those setting but need at least a 4080.  The CPU is no longer a limiting factor with Multi-threading(MT).

For DCS settings, it is up to your personal taste but running the 8kX at native resolution, I find that MSAA is not required as the best cure for aliassing is higher resolution.  If I run the HMD at 60hz, then I have the horspower to use MSAA but the quality gain is not that much.  MSAA has a very high cost in terms of GPU frametime.  On average, I increase my GPU frametime by 2.7ms which is huge and would force me to use re-projection and this is a no-go for me.  Native resolution without reprojection is the objective! 

You may notice also that my gamma setting is pretty low and this is to reduce haze.  It is a good and efficient way but you have to crank up your backlit and brightness to compensate.  

As for windows stuff, I have HAGS on with not issues and leave nvidia driver 3d setting pretty much at default except power management set to max performance.  For other software such as Pimax client, PimaxXR and OXRTK versions, see my previous post.  Running these exact versions is the key to have a smooth DCS MT experience. 

Some additional info about OXRTK:  I do not overide the resolution but use Fix Foveated Rendering (FFR) at performance setting and CAS at 100%.

Note that the pimax client FFR does not work with DCS-MT and OpenXR. 

We all have different hardware setup and this is why it is so challenging to find that sweet spot but hope this can help.

 

Hi,

 I'm used to set the Pimax 8kx at 60 Hz, getting good performance at high settings without MR  (even with SteamVR and MSAA x2), but I wanted to try your 90 Hz settings with OpenXR (FFR and CAS), as the experience could be even better.

 The performance results were not the expected, I hardly maintain 90 FPS (instant action missions), and the DCS FPS counter says I was "CPU BOUNDED", which is strange considering that I run the MT version. I tried to see the CPU/GPU frametimes in DCS FPS counter, but no success, maybe I should try the ones provided by openxr toolkit.

 In any case, I need to research the issue of "CPU BOUNDED", any tip? Maybe something related with the selected E-core and P-core? 

 BTW, my rig is composed of a 13900K (@5.6 GHz) and 4090 (slightly overclocked)

Thanks

Edited May 21, 2023 by Nahemoth

[WipeUout]

11 hours ago, Nahemoth said:

I tried to see the CPU/GPU frametimes in DCS FPS counter, but no success, maybe I should try the ones provided by openxr toolkit.

Use the OXRTK FPS counter, it will give you the right picture.

 

11 hours ago, Nahemoth said:

In any case, I need to research the issue of "CPU BOUNDED", any tip? Maybe something related with the selected E-core and P-core? 

Does not make any sense.  I have the same CPU and my CPU frametime stays around 5ms most of the time wich is way bellow 11ms (90 FPS limit).  Do you use process lasso or something similar to assign core affinity? This is not required anymore with DCS MT... or you might have something running in the background that uses your CPU?  

 

11 hours ago, Nahemoth said:

The performance results were not the expected, I hardly maintain 90 FPS (instant action missions)

You should be able to maintain 90FPS in 95% of the time.  As an example, when I run the A-10A Caucasus instant action mission (close air support) my FPS drops below 90 only when CBUs explode within my filed of view.

Speaking of FOV, I use normal since I wear glasses and wide FOV is completely useless for me.  This will be more taxing for your system if you use the widest FOV.

In any case, you should have at least 10% better performance than me with my 4080!