DCS VR perfomance on lower spec PC.

[Wolf1One]

First of all, sorry for posting in this sub-forum but for some reason it only let me create a topic in here.

I would like to state my specs first:

i7-4790k OC @ 4Ghz

32 GB DDR3

8GB Zotac GTX 1070

1TB SSD Samsung 860 EVO

Oculus Quest 2 Headset

Logitech X52 non-pro HOTAS setup.

 

And now my backstory and issues with DCS:

I've picked this sim up in December 2021 and invested quite a bit of money into modules and hardware because I wanted the most decent and affordable experience with DCS. I absolutely love the idea behind DCS world and I totally regret it being as faulty as it is right now. On my display the game runs awesome even in crowded multiplayer servers and it's an overall decent experience but everything changed when I got my VR headset. At first it was a horrible mess, low fps, insane stuttering everywhere, blurry image, all the good stuff. After about 3 weeks ~ 1 month of searching the web and tweaking every possibility I managed to get it working at around 30fps but only in certain areas and situations. Framerate wise it is a huge downgrade from what I've been playing on the displays and it is very disappointing due to several issues.

1. Random frame drops for no reason - In order to get it back to stable fps I have to ALT-TAB the game and take off the headset and put it back on my face, this sometimes works the first time but generally I repeat this process until framerate comes back to normal (around 30) - This issue is by far the most immersion breaking and frustrating (I've tried every workaround I found on the web but NOTHING fixes this issue.

2. Micro-stutter while flying low and while looking to the sides. While flying high up the framerate is stable until issue no.1 pops up (happens 1/3 sorties)

3. Extremely low loading speed on any mission (5-7 minutes) after launching the game. I can live with this but a couple of months ago this wasn't happening (I'm guessing it's either a windows update problem or DCS update problem)

 

I don't expect any solution to these problems as I've found that a lot of people experience them, even people with NASA supercomputers so whoever wants to bash my poor man's rig can take a very long hike (for lack of a forum accepted slur).

I only made this post to state my disappointment with ED's low regard towards VR users, since these issues date years back(believe me I've googled everything DCS VR related).

From where I stand, after playing VR flight simulators I cannot go back to playing on the monitors, it just doesn't cut it.

I also refuse to invest any more money in DCS modules even if I wished to precisely because this lack of performance with VR and the complete disregard of ED for making this a priority instead of mass producing money-making modules.

Sad story is the fact that DCS World means monopoly on the modern combat flight sims as it has no real competitor (BMS doesn't support VR)

I see that Vulkan was announced years ago but no signs of it even in 2022. Maybe in 2050 we'll have Vulkan API and multi-thread. Until then it seems that lowspec users such as myself will stick to IL2, because by some weird voodoo, that game works buttery smooth and looks perfect with maxed out settings, something that I feel will never be the case with DCS World. Shame.

/endrant

 

 

[SharpeXB]

DCS is a complex simulation game that wasn’t really ever intended to run in VR. The challenge stems from the fact that it models or draws so many objects over such large distances. Games which appear to run better simply don’t draw the number of objects or have such complexity. 
A game like this is never going to run well in 3D at high frame rates. And an upgrade to Vulkan or multi-core isn’t going to triple the game’s performance. The best solution for DCS is to run it in 2D.

[Wolf1One]

I agree but VR ruined it for me... It's one thing to be in the cockpit and have 1:1 head tracking and another thing completely with a janky, unreliable TrackIR on a flat screen. Ffs I can't even follow an enemy with my sight with my current head tracking solution due to jitter let alone make good use of any HMD. I think a lot of things are possible in 2022, technology wise but it requires focus, time and money... It is possible since other simulators outperform this one in a ridiculous manner (IL2 for example) 

I ain't going back to 2D sadly and I'm saying this with a broken heart. Sure it looks awesome but the feels are zero and it's an incomplete experience. 

[Qiou87]

I get that VR is the only way to go for you, I truly do because I feel the same way. However I have the possibility (financially) to invest into it and justify this decision I have taken to never go back to flying on pancake - mostly because when I try it, when creating a mission just to test a trigger for example, I find it boring as hell.

There are a couple of things I want to point out. I started in VR in DCS with a 1070Ti and a Rift S a couple of years back. Both are similar to your current setup and allowed me to play around 30fps with relatively low settings, however I believe the Quest 2 has more issues in DCS due to the fact that it is primarily a wireless headset. With a computer that has limited power, I would think having a headset with a little overhead as possible (maybe using OpenXR, instead of something from Oculus or SteamVR) would help tremendously.

To run decently in VR, you need a LOT more power than on a screen, because you are calculating 2 view points (left/right eyes) and in a higher definition than most screens as well. On top of this, the headset position is constantly shifting on 6 axis (because your head moves a little bit all the time). This is greatly different from a fixed view, only panning on 1-2 axis at a time using controls or trackIR.

It is easy to lay all the blame on the devs, but in my opinion this is flawed. Most games I have played that looked good in VR had very limited scenery and field of view (you can only go in certain areas and cannot see beyond 50-100m). In DCS, you can go anywhere, have many AI and human players around you engaging each other, and doing so at sometimes great distances. All of this requires a lot of power, no matter how you put it. There are non-combat flight sims out there that don't manage to be a lot smoother or look a lot nicer than DCS in VR, even with much larger budgets. I say this with a lot of flight hours in VR in a popular flight sim from a famous editor of operating systems.

Flight sims in general are some of the most demanding computer games. VR is probably the most demanding for graphics cards. Combine both, and now you are asking the devs to make it run on a 6-year old PC. Seems a bit ambitious.

Edited June 20, 2022 by Qiou87

[edmuss]

There's hope yet but it will involve making some compromises

DCS VR is a fickle beast and it's possible to generate relatively smooth gameplay (certainly in single player) with moderate hardware; however it is not plug and play and there is a lot of time to invest in tweaking.

Jump into the VR subforum and have a look at the openxr thread, intended for wmr headsets but it has performance and functionality benefits over the other runtimes.  Are you running the oculus or steamvr runtimes?

With the Q2 you might be struggling a bit at full resolution, however with the openxr runtimes you can reduce the resolution, apply upscaling and foveated rendering, all of which will claw back those precious MS of frametime.

edit: the frame rate tanking in VR seems to be linked to low VRAM, I have 8GB on my 3070 and in steamvr it's a constant issue, the first flight will generally be ok but subsequent flights will kill performance till DCS is restarted.  In openxr the problem is almost entirely eliminated due to much lower VRAM demand from the renderer, I think it will be the start of improving things for yourself in VR.

Edited June 20, 2022 by edmuss

[Wolf1One]

5 minutes ago, Qiou87 said:

Flight sims in general are some of the most demanding computer games. VR is probably the most demanding for graphics cards. Combine both, and now you are asking the devs to make it run on a 6-year old PC. Seems a bit ambitious.

It has moments when the performance is just perfect, even on my machine. What's obvious indeed is the fact that needs a lot of polish and optimization. I think the random fps drops bug for example can be addressed somehow on the developer side. 

[Qiou87]

5 minutes ago, Wolf1One said:

It has moments when the performance is just perfect, even on my machine. What's obvious indeed is the fact that needs a lot of polish and optimization. I think the random fps drops bug for example can be addressed somehow on the developer side. 

Your CPU is probably a huge bottleneck in these scenarios. Oculus has a tool to analyze FPS and especially frame times to let you know, in these instances, which component (CPU or GPU) is the culprit. You have an old CPU ; considering DCS used mostly one core, if you have people shooting cluster bombs or multiple units spawning, engaging each other etc. this can become too much for your CPU and you get this "drop". I used to get similar drops on my Ryzen 2600X ; happy to say that switching to a modern CPU (Ryzen 5600X) completely made these drops disappear even in heavy missions. Modern CPUs have cores that perform more operations per cycle (IPC) and even at the same frequency, they are simply much faster on a single core.

 

EDIT: also what Edmuss said about OpenXR, if you are able to run this for your Quest 2 there is a chance for higher FPS.

Edited June 20, 2022 by Qiou87

[Wolf1One]

4 minutes ago, Qiou87 said:

Your CPU is probably a huge bottleneck in these scenarios. Oculus has a tool to analyze FPS and especially frame times to let you know, in these instances, which component (CPU or GPU) is the culprit. You have an old CPU ; considering DCS used mostly one core, if you have people shooting cluster bombs or multiple units spawning, engaging each other etc. this can become too much for your CPU and you get this "drop". I used to get similar drops on my Ryzen 2600X ; happy to say that switching to a modern CPU (Ryzen 5600X) completely made these drops disappear even in heavy missions.

 

EDIT: also what Edmuss said about OpenXR, if you are able to run this for your Quest 2 there is a chance for higher FPS.

 

Couldn't get OpenXR to work sadly. Tried with OpenComposite (which works with everything else other than DCS like a charm) but it crashes on launch.

[edmuss]

5 minutes ago, Wolf1One said:

Couldn't get OpenXR to work sadly. Tried with OpenComposite (which works with everything else other than DCS like a charm) but it crashes on launch.

It should work just fine, stick with it as the benefits are pretty considerable

Have a search through the thread for the crash error and you should find a fix.

[Wolf1One]

15 minutes ago, edmuss said:

It should work just fine, stick with it as the benefits are pretty considerable

Have a search through the thread for the crash error and you should find a fix.

Searched a lot but had no luck. If you can point me out to the thread you are referring to that would be awesome. I found this instead: 

 

[draconus]

You paired mid-level headset with low performance PC and very high demanding software - what did you expect? You can adjust pixel density and gfx options until you find a compromise quality vs fps.

I started VR having GTX970 but I knew what to expect - still great experience and I'm not going back.

[Wolf1One]

2 minutes ago, draconus said:

You paired mid-level headset with low performance PC and very high demanding software - what did you expect? You can adjust pixel density and gfx options until you find a compromise quality vs fps.

I started VR having GTX970 but I knew what to expect - still great experience and I'm not going back.

If I could get it to run via OpenComposite I'm sure it would work like a charm, just like the other games. At the moment, all settings combinations I've tried are borderline unplayable due to microstutter while flying low and random framedrops at any given point(issue no.1). I didn't expect it to be easy but the quality compromise should pay off while for the moment it does not. In this current state I find it somewhat playable but terribly frustrating due to the aforementioned issues .

[edmuss]

1 hour ago, Wolf1One said:

Searched a lot but had no luck. If you can point me out to the thread you are referring to that would be awesome. I found this instead: 

 

It's one of the biggest threads in recent times on the VR forum

 

[Wolf1One]

11 minutes ago, edmuss said:

It's one of the biggest threads in recent times on the VR forum

 

Been trying to follow the instructions but the Skatezilla app doesn't work as it should and I wonder if I need DCS Standalone to use it properly because at the moment I'm running the steam edition. Thanks m8.

[edmuss]

I've never used the skatezilla app, just the ED supplied batch files (on the FAQs section of the website if you don't have them) to do the update/clean/repair; I do use standalone though.

You can convert steam module licenses to standalone licenses (but not vice versa) so apart from the faff of downloading the latest version again it's not a problem.  If you're not using the open beta version of DCS I'd recommend you do so as there have been a number of VR performance improvements (couldn't tell you what they are but FPS has improved recently).

[Wolf1One]

1 minute ago, edmuss said:

I've never used the skatezilla app, just the ED supplied batch files (on the FAQs section of the website if you don't have them) to do the update/clean/repair; I do use standalone though.

You can convert steam module licenses to standalone licenses (but not vice versa) so apart from the faff of downloading the latest version again it's not a problem.  If you're not using the open beta version of DCS I'd recommend you do so as there have been a number of VR performance improvements (couldn't tell you what they are but FPS has improved recently).

I am on the open beta branch and I will try switching to standalone as well tonight, hope it works.

[SharpeXB]

8 hours ago, Qiou87 said:

On top of this, the headset position is constantly shifting on 6 axis (because your head moves a little bit all the time). This is greatly different from a fixed view, only panning on 1-2 axis at a time using controls or trackIR.

TrackIR is actually 6DOF as well. I can’t imagine this has much effect on performance though. 

[draconus]

41 minutes ago, SharpeXB said:

TrackIR is actually 6DOF as well. I can’t imagine this has much effect on performance though. 

It does not affect performance - basic functionality.

[Wolf1One]

10 hours ago, edmuss said:

I've never used the skatezilla app, just the ED supplied batch files (on the FAQs section of the website if you don't have them) to do the update/clean/repair; I do use standalone though.

You can convert steam module licenses to standalone licenses (but not vice versa) so apart from the faff of downloading the latest version again it's not a problem.  If you're not using the open beta version of DCS I'd recommend you do so as there have been a number of VR performance improvements (couldn't tell you what they are but FPS has improved recently).

I managed to get DCS to launch via OpenComposite runtime after uninstalling the steam version and installing standalone with carried over modules. I cannot, however, access the OpenXR Toolkit menu inside DCS via set shortcut(it works in other games). OpenXR is active tho as it's marked with green in its interface. I can't thank you enough for motivating me to give this one last try because I got so angry with it yesterday I was very close to giving up on DCS VR. The performance has almost doubled and 95% of the stuttering is now a thing of the past, wow... Amazing! Did some extensive testing, including multiplayer and omg, it fkn WORKS, the stutter is gone!!! Only one bug still remains, from time to time FPS drop hard and I need to ALT-TAB and take off my headset and put it back but it seems that the intensity of this occurrence is lower now. I enjoyed myself tonight for the first time with this headset in DCS. OpenXR and OpenComposite are a MUST HAVE for everybody who encounters these depressing problems! Cheers guys! I'm off to get some gun kills 

[edmuss]

Awesome that it's opened up so much extra performance!

To alleviate the performance tanking try to reduce some settings that eat up VRAM, that would mainly be textures and shadows I think. Also worth while looking at lower texture mods, things like the tree mods by @Taz1004 reduce memory usage whilst looking better.

Once you've gotten the ingame toolkit menu to load then you'll have access to FSR upscaling which will unlock another chunk of performance. I'm not sure of ins and outs of getting the toolkit to show in the quest but it's possible.

Edited June 21, 2022 by edmuss

[Wolf1One]

Latest update: I got the toolkit to launch with DCS properly. It appears that despite my added command lines to the DCS shortcut, it still launched in Oculus runtime. The trick was to launch DCS via Skatezilla with correct parameters. The framedrop bug is gone for good as it appears that it's an Oculus runtime bug and not a DCS bug. Insane how much effort you need to put in tweaking VR :))

[Flappie]

Thanks for your feedback.

A friend has the same issue you were having. Could you please explain exactly how you did solve your issue? Do you only use SkateZilla's GUI? or did you downloaded the batch files edmuss told you about? Which parameters are you using?

[lev-kusanagi]

On 6/20/2022 at 12:23 AM, SharpeXB said:

DCS is a complex simulation game that wasn’t really ever intended to run in VR. The challenge stems from the fact that it models or draws so many objects over such large distances. Games which appear to run better simply don’t draw the number of objects or have such complexity. 
A game like this is never going to run well in 3D at high frame rates. And an upgrade to Vulkan or multi-core isn’t going to triple the game’s performance. The best solution for DCS is to run it in 2D.

the future of flight simulation is in VR. it doesn't matter how "complex" dcs is, non single thread process version of dcs , properly coded will run fine. i don't understand these defeatist arguments.

 

Edited October 31, 2022 by lev-kusanagi

[SharpeXB]

2 minutes ago, lev-kusanagi said:

the future of flight simulation is in VR

The future of VR is social media…

[lev-kusanagi]

6 minutes ago, SharpeXB said:

The future of VR is social media…

oh not at all. i added some context to my previous post