To get a somewhat useful VR mode in XP1150 Vulkan, if you cannot get acceptable performance with the normal setting, without using any tweaks, try the mods below.
The XP settings listed below are a must for the PiMax 8K to be able to make out, read, some of the text on the Instrument panel.
System tested on Win 10 64, i7-8700 CPU @ 4.43GHz (12 CPUs), 16GB RAM, DirectX 12, GTX 1070, 8GB, Drv 442.19, FireStorm, GPU Clk Boost 1803 (120) MHz, Mem 4006 MHz, 4K Mode.
XP11 settings, Set up an .SIT with Default Scenery,C172 6pack, No AI, Vis 50 SM, No clouds, 2:20 Zulu, KSNA 20R. Settings for brightest colors: Visual High (HDR), Texture>Maximum>AA>4xSSFX, Window mode, FOV 50%, if that does not give you 70+ FPS in VC / 2D or 23+ FPS or more using 3jFPS, in VR, try Visual Medium, Texture>Max, AA>8x, if you cannot get at least the above FPS it's likely that you will Not get a very good experience.
PiMax 8k headset using SteamVR.

1-Download and Install 3JFPS in X:\XP11…\Resources\plugins\FlyWithLua\Scripts.
If you cannot get an acceptable performance with just 3jFPS you can try to change the vr/use_interleave=0, see below.
2-Download and Install DataRefEditor https://github.com/leecbaker/datareftool/releases and place the Win.xpl into X:\XP11..\Resources\plugins.
Start XP go to Menu> Plugins>Data Ref Editor>Show Art Controls, scroll down to vr/use_interleave = 1.0 and change, 2xLClick on it change to 0.000000 and Return. Use Delete viewers to remove the Data refs text from screen. Go into XP11>Settings>Graphics> Enable Vulkan and Restart.
At this point you can load your .sit, make sure your VR is On and all set up Software wise, in XP>Settings, VR Hardware>Enable Mouse and VR.
While I still get some slideshow with this system when I look under the wing, at the main wheel in 172, it’s somewhat useful, without having to go into the LR extended real time <20FPS.
I will try my other, more powerful GTX 1080, 32GB… system at some point but it is not acceptable, as is, without any of the modifications listed above.
Both systems worked well without mods in XP1141.
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