SteamVR Render Resolution Has Made DCS Playable Again

[JimmyWA]

I've been searching to see if this topic has already been discussed, but could not find it anywhere - the search words return at least 40 pages, and I stop after around the 5th page -  but I wanted to share this.

I have a top of the wazza PC with an older RTX2080ti video card, which I overclock. However, even by setting all the DCS video settings to low and no shadows, my FPS could be as low as 8. I then stumbled across a couple of articles, and in SteamVR went to settings, and changed the Render Resolution from Auto to 48%. This sets it much closer to what the actual resolution of my HP G2 is. This means in the Per App setting, I leave DCS at 100%.

The results are startling. I am now getting around 60fps on both single and MP.

I then added shadows, and even MSAA, and I was still getting nearly 60 fps.

 

I can fly in DCS using VR again!

[Eugel]

42 minutes ago, JimmyWA said:

and changed the Render Resolution from Auto to 48%. This sets it much closer to what the actual resolution of my HP G2 is. This means in the Per App setting, I leave DCS at 100%.

I would do it the other way round, depending on whether you play other VR games or not. I always leave the standard resolution at 100% and only adjust the per app resolution. 
But yeah, I did the same thing when I was on my 1080 Ti - 48-50% resolution.

It´s not ideal as the picture becomes quite blurry, but it gets you playable framerates...

[edmuss]

Switch to openxr and with a well tuned rig you should be able to get better framerates at higher resolution and settings.

My 3070 is slower with less VRAM and running the G2 at 2900 wide (about 85-90%) and medium high DCS settings I can still generally pull 60-70 fps. This is without motion reprojection but openxr is far smoother all round so it's possible to play at 45-50fps without too much hassle

Edited June 27, 2022 by edmuss

[Wizard1393]

2 hours ago, JimmyWA said:

in SteamVR went to settings, and changed the Render Resolution from Auto to 48%. This sets it much closer to what the actual resolution of my HP G2 is.

I think it's been concluded that this is not correct. The resolution displayed in SteamVR when adjusting the resolution percentage slider is not your actual resolution of the panels on your Reverb, as the original image is shrunk and distored to be displayed correctly in the VR set. Setting anything lower than 100% is actually downscaling the image.

[PLUTON]

Hello everyone,
Can setting the G2 to 2900 wide (around 85-90%) be done in Openxr?

[edmuss]

14 minutes ago, PLUTON said:

Hello everyone,
Can setting the G2 to 2900 wide (around 85-90%) be done in Openxr?

Yes, use the system tab of the openxr toolkit ingame menu and use the resolution override (needs a restart of DCS).

[PLUTON]

Here I made a flight with the setting at 2900
and I have my fps which has dropped and I have stutters so
I put the settings back as before and everything is back to normal.
(I should have at least tried).
On the other hand I am always obliged to restart DCS after each
mission because otherwise if I don't do it the next mission does not exceed 5 or 6 fps.

Merci pour tous vos conseils et de prendre le temps de me répondre 

[edmuss]

Had you previously set a resolution override using the openxr tools desktop app or is it set to default resolution?
The default resolution will calculate the recommended display resolution for you based on how much VRAM your GPU has (the calculation is based on the three render buffers with 4xMSAA applied shouldn't exceed 10% of VRAM available).

For my 8GB 3070, by default it sets it to around 2600 wide; I prefer to run slightly higher resolution rather than use MSAA as it improves the clarity of the image (I find MSAA makes it a bit blurry in the cockpit).  If you had it set to default before and that was calculated to a number lower than 2900 then your performance will obviously suffer if you override it to the higher amount.

It sounds as though you're running low on VRAM (DCS appears to not release VRAM properly and causes massive performance loss), try reducing texture and shadow settings to see if it alleviates the issue.

[PLUTON]

answer for mr edmuss

No in 0penxr desktop the resolution override is on off, and I always use it on off
I have a 2080 8gb and I think it does quite well.

 

[edmuss]

So before you set the resolution override to 2900 wide in game it will have been running at around 2600 which would explain your performance drop; you should be able to check the current render resolution on the second tab of the openxr tools desktop app

The 3070 is faster than the 2080, it's within 1-2% of a 2080ti so I would expect your GPU to be happier with slightly lower resolutions, fortunately openxr seems to downscale pretty well.

 

[PLUTON]

It's true that my 2080 runs well and I shouldn't complain about the performance I get on
all my maps but here I am like everyone has the more we have the more we want.
Just wait for Razbam to optimize SA and it will be great.

In addition you made me know Openxr
which helped a lot
thank you edmuss