B4ron

Reducing fps to almost 1/2 of what your System is capable could not be the solution! If I reduce to 36 in VR albeit my system is capable of doing 60, I also get no stutters but no fluent picture when moving as well.

You can refer to this topic:

DCS was assigned to the external GPU already. I already had virtualization disabled as well. I tried disabling memory integrety but still no change. When I'm in game and disable (and also after re-enabling) the iGPU in device manager, the frametime spiking is gone according to the DCS frametime graph. However the stutters are still present. As I assumed above, it seems to me as if the shader cache is not used. Can that be the case?

Hi flappie. Thanks for the hint. I tried with disabled iGPU but strangely I only got 18fps with an GPU utilization of only about 25%. Don't really have an explanation for that. The external GPU doesn't have its own interface, maybe the signal is routed over the iGPU to the display port my VR headset is connected to?! I recently also tried (among many other things) booting in safe mode as you sometimes recommend but still stutters, so they're also not related to some external process.

I'm on an AMD card where that option doesn't exist. I tried setting "flip queue size" in registry which is the same for AMD cards but no joy.

This is quite similar to what I see. All is smooth and when moving my head into some busy areas or towns there are stutters. After 1 second or so looking into that direction the stutters disappear also when slightly moving the head. The stutters come up again when looking into another problematic area.

Tested with terrain object detail and forest detail and forest visibility to max and the stutters got even worse. Also shadows off an on again made no difference.

Stutters are basically caused by frametime spikes. Each VR headset is calling frames from the graphics engine buffer in fixed periods defined by the refresh rate of the head set and hence using some kind of VSync IMO which cannot be turned off. If the buffer cannot be updated by the graphics engine fast enough to meet the frametime period and the frame buffer is empty (which happens when you're not reaching your headsets refresh rate) it calls and presents the "old" frame again which can be noticed as stutter. Capping framerate or motion smoothing (which basically does also cap framerate) increases the call period which gives the engine the chance to meet the call frequency and hence give you a smooth experience. If you are lowering settings now you may increase the output frequency of the engine (aka FPS) which might have the same effect. So, for a stutter free experience the only important thing is, that your maximum frametimes (aka spikes) do not exceed the call period of your headset (when the buffer is empty). I am getting frametime spikes every 4th or 5th frame as I pointed out in this thread which are 3 times higher than the frames in between. And yes, you can lower your settings or refresh rate to a point where those spikes don't come into account anymore, but you'll hardly underperform your rig. So, whatever causes these spikes needs to be fixed. OpenXR Toolkits developer fps overlay shows me high "wait" times. The DCS fps counter shows that the spikes are caused by "Simulation". So I assume the graphics card is waiting for something from DCS to complete the spiking frame. Can anyone also do a frametime record in VR (with uncapped framerate and motion smoothing off) in order to see if others have the same behaviour?

Ok, I'm glad at least that other do have similar problems, too and it doesn't seem to be up on my setup. Ground shadows are always off in my settings, I tried "on" but no difference. I also tried shadows off but still stutters. I lowered every single setting but no joy. I even tried at low settings but still stutters. I haven't tried maxing out details and visibility since that seemed unlogical to me hence the engine has to load even more data, but I'll give it a try and report back...

Stutters are still present after the last update. I tried literally everything to get rid of the stutters, nothing helped. I had smooth performance before the MT update. Now the stutters are present as well in the ST version. There are some (strange) facts: - There are frametime spikes each 4th or 5th frame when framerate is not capped (normally 11-12ms, each 4th or 5th frame around 30-35ms - this might be due to the VR software is forcing VSync). Usually I fly in VR with 90Hz and framerate capped to 45fps without motion smoothing. When not capping I get 60-65fps on populated servers. - Alt-tabing out of DCS completely removes the stutters and completely smooths out frametime - The stutters only happen when looking into populated areas or areas with many units on populated MP servers. The stutters disappear after a few seconds looking into the same direction. - The stutters appear as when VRAM would be completely filled but actually it is filled less than 50%. - Reducing DCS settings to low or VR and reducing PD does not help. Due to those facts it seems as there is a problem with shaders IMO. The stutters appear the same as after deleting shader cache, when shaders are cached for the first time again, but permanetly. It seems as if DCS is not using the shader cache, but always renders new ones... null dcs_frame_mt.log DxDiag.txt dcs.log

No, I never realised those effects.

I think it's not working, since I was able to see some scenes disappear at the very edge of my Pimax headset when it was enabled in ST. This effect is not present in MT. I would appreciate it being activated in MT since it saved some frametime.

Same here. I get stuttering on populated MP servers when looking in certain directions, especially towns which has not been there on ST. However the FPS counter shows stable 45 FPS with reprojection and lower than necessary frametimes. Decreasing the settings hasn`t helped.

Unfortunately not myself since I disabled track recording. I can ask on discord...

+1 The engine did not seize completely when I went into a dive at about 2700rpm but lost its power. I was able to make it back to the airfield with reduced power. @Night Owl and others also reported engine issues on discord but with the engine completely dying after throttling back from 3000rpm to 2700rpm.