I’ve just added the following in the 2nd post:
[Update 26NOV2020 - FS2020 1.11.6 (Update 7)]
I’ve been further exploring optimization opportunities since my last update and I’ll update my settings screenshots and some comments. In short, instead of trying to get the highest fps, I’ve approach the settings differently in trying to get the smoothest fps so that I can eliminate most of the stutters (unrelated to juddering). Therefore since my last update I’ve been trying to stay as much as possible locked to 30fps while making sure there is not CPU/GPU sync hiccup intervening and dropping the fps further.
In effect, I’ve discovered there is a fps-locking feature with FS2020 which is limiting the fps to an integer divisor of the Valve Index refresh rate (for example at 90Hz it locks to 45, 30 or 22.7fps). I was even using this to my advantage when for example I was able to push 42fps, in setting SteamVR to 80Hz in order to lock to 40fps, otherwise it would lock to 30 only.
In approaching the settings to get a smooth 30fps instead of a constantly alternating 22.7/30/45 fps depending on the context, I’ve noted it is perceivably still smooth enough in most conditions. Of course at 30fps don’t wish you’d also get smooth updates when looking 90 deg to the side during takeoff close to the ground.
The best part of this is in order to achieve the goal of locking in to 30fps you have to ‘saturate’ the GPU so that you’re heavily GPU limited. This is good because it means you can raise your visuals and have a better looking view! Beware, not all settings play nice with this strategy and here is a short list of my findings for you to try out if you want until I update my post in the coming days:
NVidia CPL Threaded Optimization must be ON (not AUTO). It helps a lot reducing the GPU/CPU sync slowdowns/spikes I can monitor clearly with fpsVr.
I don’t see much performance difference if any between NVidia CPL Texture performance and the other Trilinear optimizations, therefore I’m favoring Quality now (until I also cross check against “My 4K Settings”).
I’ve disabled GPU Scheduling also for now. I’m not sure it gives any advantage yet and today’s tests were giving better results overall. It is quite subjective at this stage though.
Render Scaling is better 100% or 70% (this is CPU/GPU dependent). When using any other value I can see the CPU taking a lot of processing time, constantly, whereas with 100% for example it is freeing the CPU for other things. I’ll therefore probably just keep the ‘legibility’ option which is using 100% TAA and adjusting render resolution in SteamVR instead. NB: for my 30fps goal, I also use 100% render scaling in SteamVR and I get a very nice and sharp picture!
Ambiant Occlusion, even if LOW, seems to be causing a lot of CPU activity when close to the ground mostly. It is bad to have stutters on short final and in many of my tests, I can get rid of most of these with AO to OFF.
I suspect the fps-lock feature I’ve mentioned above is either FS2020 hard coded or OpenXR (I never noticed such behavior in other games but I might have not paid much attention either). Although I could select 80hz or 90hz with update 6 and choose whether I’d prefer getting 40fps or 30fps, with update 7 I find anything other than 90hz is causing a lot of CPU/GPU sync issues (red spikes in fpsVr). It depends on the load of course and therefore it depends on the aircraft you’re flying and location.
With these I can raise some important settings (SteamVR 100%, TAA 100%, Terrain LOD 100%, Buildings High, Trees High, Clouds Medium) and get a smooth flight over Los Angeles with lots of clouds and multiplayer aircraft around me. There are even times I can push clouds to HIGH and this is really looking good considering it is rendering 2x2016x2240 pixels!
However I still can’t enable motion smoothing in SteamVR because it is creating too much wobbling at 30fps. So although I can see juddering (this is what makes you see the image de-doubling when looking to the side for example) I’m fine because most of the time I’m flying I’m not making constant aerobatics figures either.
I hope this will give you some additional opportunities on your hardware, and I’ll update my screenshots and the explanations with them in the coming days!