Is a DX12 VRAM fix feasible in MSFS?

[regis9 4,038]

I’m curious for thoughts on whether it’s a reasonable expectation that the issue of extremely high VRAM usage can be fixed in a flight sim like MSFS?

I’ve experienced the stuttering causes by running out of VRAM at a lot of payware airports with a high detail airliner.  This is with a 4080 w/16gb of VRAM.

Out of curiosity I’ve started watching VRAM usage in other games and nothing else so far comes remotely close to exhausting my VRAM.

I remember when P3Dv5 went DX12 a lot of us started running out of VRAM.  At least MSFS just gets stuttery instead of crashing!  I’m not sure if X-Plane has similar VRAM usage issues.

It all leads me to wonder: given flight sims tend to be among the most demanding games on hardware, and how broad they are instead of the much more controlled environments of most other games, is it actually realistic or feasible that there’s a solution for this high VRAM usage?

I partly ask out of curiosity, but partly ask because I’m toying with the idea of selling my 4080 and buying a 4090, mostly for the additional VRAM.  If there no realistic prospect that the VRAM issue will go away (either in MSFS2020 or 2024) then I feel like the 4090 is something I want to do.  If there’s hope this issue can be addressed then maybe I’ll keep my 4080 a bit longer and see.

The technical aspects of this are a bit over my head, but I’ve read comments about how DX12 in MSFS is a beta and perhaps “rough”.

Thanks for any thoughts!

Edited October 22, 2023 by regis9

[brucewtb 250]

Out of interest at what payware airports and with what high detail airliners and MSFS2020 settings do you get stutters from maxing out you 16gb of VRAM?.  I have a 3080ti with 12 gb of VRAM that regularly gets maxed out but I am not sure that I see stutters running at 4K and most settings on ultra but AI at about 30%.  Thanks

Bruce

[Snuffleupagus 328]

inibuilds LAX does it for my 4080 at 2K. Because of that bad of performance, I haven’t bought another addon from them. It’s the only scenery that causes my 4080 to max out. 

[simon747 185]

Same here, I use DX12 and have never gone over 12 gigs of VRAM with complex airliners at Gatwick etc.

Simon

[SierraDelta 1,355]

For the record, I saw 20.4Gb at FT EHAM a couple of days ago, 4k, PSXT/RealTraffic.

[AnkH 2,282]

16 minutes ago, simon747 said:

Same here, I use DX12 and have never gone over 12 gigs of VRAM with complex airliners at Gatwick etc

I wonder how many times it must be first made clear that you state on which resolution and settings before statements like this one makes any sense? It is a lot different if you use 1080p, 1440p or 4K, and of course also which settings you use. In my case for example, I was easily maxing out my 16GB VRAM on 1440p using resolution scale 130, everything ultra and 6x6 texture supersampling. By simply turning down resolution scale to 105 and texture supersampling to 2x2 I am now almost everywhere 1-2GB below max VRAM, even on EHAM by FT with 75% AIG traffic (all packages instalued). 

[bobcat999 8,504]

I don't know if it is a VRAM thing, but it is disappointing we still have these issues in 2023. Developers need to ensure their scenery add ons maintain acceptable performance rather than just throw in the kitchen sink. 

Both the recent Milford Sound and Bora Bora scenery enhancements cause unnaceptabe performance hits on my fairly high end system. 

NZA said they were looking at optimisations but I haven't heard anything for a while. 

Edited October 22, 2023 by bobcat999

[cianpars 1,179]

23 minutes ago, bobcat999 said:

I don't know if it is a VRAM thing, but it is disappointing we still have these issues in 2023. Developers need to ensure their scenery add ons maintain acceptable performance rather than just throw in the kitchen sink. 

Both the recent Milford Sound and Bora Bora scenery enhancements cause unnaceptable performance hits on my fairly high end system. 

NZA said they were looking at optimisations but I haven't heard anything for a while. 

A bit worrying that those two sceneries are causing you problems with a system like yours Bob.  I had better stay clear of these two.

I for one prefer to limit to 30 fps most of the time as I have a smoother experience and a bit more headroom to run very system taxing addons.  My system also runs a lot cooler at 30 fps compared to 60 fps where my fans are running like the clappers.

One thing I do find is that TrackIR likes the higher fps though.

[regis9 4,038]

8 hours ago, brucewtb said:

Out of interest at what payware airports and with what high detail airliners and MSFS2020 settings do you get stutters from maxing out you 16gb of VRAM?.  I have a 3080ti with 12 gb of VRAM that regularly gets maxed out but I am not sure that I see stutters running at 4K and most settings on ultra but AI at about 30%.  Thanks

Bruce

Off the top of my head inibuilds KLAX and KJFK, mkstudios KPHL, BMW/Amsim CYUL, FlyTampa CYYZ…there are others I’ve encountered but these one immediately come to mind.  Some of the issue can be mitigated by turning TLOD down to 70 or so, but there’s still no VRAM headroom to spare.

Even flying into FSDT KORD last night my available VRAM got down as low as 700mb…now I will say that low number occurred on approach flying over downtown so perhaps that’s a bigger issue of VRAM optimization in large photogrammetry urban areas.

I wonder how much of it is a core sim issue to fix vs developers needing to ensure their scenery is optimized for efficient VRAM usage?

Edited October 22, 2023 by regis9

[Ixoye 1,837]

My 12 GB VRAM run out at most third party airports in 3440x1440 Ultra, it's unplayable for me in DX12 but works just fine in DX11 with same settings, MSFS are the only game iv'e tried that have this huge VRAM usage in DX12, something is not right, but it is a beta option after all, I will upgrade to a 4090 if the problem persists with MSFS 2024, but apparently that game will have a brand new code so there is still hopes.

Edited October 22, 2023 by Ixoye

[B777ER 2,492]

Same issue here. Have a 4080, running 4k, most setting on Ultra, TLOD 150, OLOD 200 and get VRAM induced stutters at most iniBuilds and BMW/AMSim scenery. I've given up on FG and went back to DX11 as my 7800x3d chomps through that just fine. MS/Asobo I don't think will do a bloody thing about it in MS2020 but hopefully MS2024 or I will have to upgrade to a 4090. Ridiculous that we are seeing this with 16gm of memory on a 4080. 

[tgsweat 144]

12 hours ago, regis9 said:

I’m curious for thoughts on whether it’s a reasonable expectation that the issue of extremely high VRAM usage can be fixed in a flight sim like MSFS?

I’ve experienced the stuttering causes by running out of VRAM at a lot of payware airports with a high detail airliner.  This is with a 4080 w/16gb of VRAM.

Out of curiosity I’ve started watching VRAM usage in other games and nothing else so far comes remotely close to exhausting my VRAM.

I remember when P3Dv5 went DX12 a lot of us started running out of VRAM.  At least MSFS just gets stuttery instead of crashing!  I’m not sure if X-Plane has similar VRAM usage issues.

It all leads me to wonder: given flight sims tend to be among the most demanding games on hardware, and how broad they are instead of the much more controlled environments of most other games, is it actually realistic or feasible that there’s a solution for this high VRAM usage?

I partly ask out of curiosity, but partly ask because I’m toying with the idea of selling my 4080 and buying a 4090, mostly for the additional VRAM.  If there no realistic prospect that the VRAM issue will go away (either in MSFS2020 or 2024) then I feel like the 4090 is something I want to do.  If there’s hope this issue can be addressed then maybe I’ll keep my 4080 a bit longer and see.

The technical aspects of this are a bit over my head, but I’ve read comments about how DX12 in MSFS is a beta and perhaps “rough”.

Thanks for any thoughts!

I upgraded to a 4090 for this reason. I got tired of maxing out VRAM.  I kept upgrading from 3080, 4070, 4080 until i just bit the bullet and purchased the 4090 and its been the best thing i've done.  Highest VRAM I see now is about 18gb wtih maxed settings at inibuilds airports and no stutters.  

Edited October 22, 2023 by tgsweat

[Bert Pieke 7,591]

6 hours ago, SierraDelta said:

For the record, I saw 20.4Gb at FT EHAM a couple of days ago, 4k, PSXT/RealTraffic.

What happens using dx11?

[bobcat999 8,504]

6 hours ago, cianpars said:

A bit worrying that those two sceneries are causing you problems with a system like yours Bob...

I for one prefer to limit to 30 fps most of the time as I have a smoother experience...

...One thing I do find is that TrackIR likes the higher fps though.

Yes, as you say, I really would like to hold at 60 fps due to my tobii head tracker.  This is at 4k DLSS ultra.  Maybe I am expecting too much, but everywhere else is fine, even over some big cities and airports.

Both of those scenery addons are a bit 'choppy' for me rather than being an out and out frame rate issue.  If I look directly at Milford Sound airport or Bora Bora main mountain from about a mile out, it isn't very smooth at all. A shame!

I believe NZA were looking at splitting some .bgl files (e.g. static aircraff) to help performance but I haven't heard anything recently.

[SierraDelta 1,355]

1 hour ago, Bert Pieke said:

What happens using dx11?

I honestly don’t know Bert, haven’t used DX11 since Frame Generation became a thing.