DX12 3x less FPS than DX11 - same settings

Hello Guys

I updated to last NVidia drivers (517.48) and I´m still facing a big drop (3x) on FPS when using DX12 comparing it to DX11.

Based on developer FPSs panel, I can see that VRAM use for DX12 appears to be the problem, its using about 7GB of my 4GB video card.

My Spec:
Device name Studio-Eros
Processor 11th Gen Intel(R) Core™ i7-11800H @ 2.30GHz - 4.60 GHz
Installed RAM 32.0 GB (31.8 GB usable)
System type 64-bit operating system, x64-based processor
NVIDIA® GeForce RTX™ 3050 (4 GB GDDR6) 128 bits

In-game settings:



Result with DX11, DLSS - Performance

Result with DX12, DLSS - Performance

Is there someone facing the same behavior? Or someone has some tip to solve it?

[]´s
Eros

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I’m in the same boat. DX12 is even more unusuable than it was prior. It fixes visual glitches and broken ground textures I was seeing before, but performance is abysmal due to excessive VRAM usage.

I have a feeling that for some of us, that memory optimization that’s supposed to kick in when it detects the new nVidia drivers isn’t working. Notice in your screen shots that it’s using more VRAM than you have available. It’s doing the same for me on my 3070Ti, using about 2GB over what I actually have.

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Does the 3050 only have 4gigs? You will struggle if so

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4 GB is low, but under DX12 users of those GPUs have little issue.

With a texture resolution on Ultra??

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Yeah, Ultra is WAY too high for 4GB.

I’ve found that on dx12 with the latest xx.48 Nvidia GRD driver, a seemingly random sequence of going between full screen to windowed mode (alt+enter) on all three of my sim monitors will sometimes get the sim to pass a kidney stone and it will run a lot faster. So from like a choppy 9-12fps up to a much smoother 24-34fps. Also, sometimes escaping to the menu and back or moving a graphics slider one notch then back and saving also moves the stone along. No rhyme or reason really. It just seems to work sometimes.

No actual changes are made in this head rubbing, belly patting sequence. So I’m pretty sure the sim/driver/PC are always capable of the faster speed.

Another thing to note is that the GPU (and CPU) usage remain >90% whether it’s “high” or low FPS. The big difference is the GPU temperature… when it’s slow FPS, I see about 50degC and when it’s fast(er) I see around 60degC, so it’s working much harder with it’s >90% usage. This is a hybrid cooled EVGA 3080-10G FTW3 card, by the way. VRAM usage doesn’t seem to affect the discrepancy between the faster and slower FPS. It’s usually between 7-9.5GB used, per the dev mode FPS overlay.

Your mileage may vary of course but it’s probably worth a try if you are seeing such low frame rates.

Your out of vram arnt you? You’ll have to drop right down on those ultra settings.

I made some changes on settings just to test, and it appears not directly related to the ultra settings, because using DX11 even on ultra I have 3 times more FPS than DX12.

Please find bellow the result using “Medium” on global render quality, DX11 still much faster then DX12, of course the FPS is better but the gap between DX11 and DX12 still there.

DX11:

DX12:

Thanks
Eros

I saw my VRAM spike to 30gb with 6gb being allocated into shard memory meaning ddr4…

The over allocation is not good. It should just stop loading stuff.

It can be fixed with just turning down terrain level of detail. Go to a common big city + int airport and dial in the LOD and you should be fine.

DX12 performance is great otherwise.

With a 4GB graphics card on mostly ultra settings, frankly I’m surprised you’re not getting 12 FPS on DX11 as well.

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Even with my settings all at LOW (and a restart of the sim so the new texture setting kicks in), under DX12 it tries to use about 2GB VRAM more than the 8GB I have available on my 3070Ti.

No memory allocation issues under DX11 though. I can run all ultra without any GPU issues and it rarely even fills the 8GB available.

There’s a serious issue with their DX12 memory management. And whatever it is they claimed they enabled that was supposed to kick in with the new nVidia driver obviously is not working.

2 Likes

Look at the memory usage in both of those screens and you will find your answer. You are maxed out in DX12 and not in DX11. When you use all of your VRAM you start using your system RAM which is a lot slower hence the performance loss. DX11 and DX12 aren’t the same so don’t expect the same results. DX12 uses more VRAM

That doesn’t matter, your VRAM usage still exceeds your capacity. You have too many settings on Ultra for a 4 GB low end GPU. This is a classic example of trying to run high-end settings on a mid to low-end system.

You should be using the Medium global preset as a starting point and lower more settings based on this latest screenshot until your VRAM usage is reduced.

In my opinion, you shouldn’t be using DX12 when this VRAM limited.

stutters continuously after SU10, it needs to be fixed with a new patch because it’s really annoying when it stutters, especially when landing or starting even in the air, do you have a solution for that

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I’m not getting stutters myself but overusing memory is a good place to look like the OP will have to. CPU usage as well

DirectX12 seems fine in 2D mode for me but it’s great in VR. I have a 3090 so don’t experience the VRAM issues some are having but I find that performance in SU10 is worse than in SU9. Specifically with DirectX12 and DLSS quality I can run and 100 percent render both in game and in openXR developer tools and have excellent visuals but some ground stuttuer. Or I can run at 90 percent render in the OpenXR developer tools and have smooth performance but a weirdly blurred cockpit with instruments not quite readable.

I’m going to try going back to DirectX11 and using the TAA and the OpenXR toolkit again with FSR.

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dx12 will help only if the system can handle the load to start with, your just pushing that laptop beyond what it can handle
i dont really have any clue why dx11 is so much faster other than maybe your gpu just isnt optimized for dx12? (total guess in the dark)
either way something is not right but i have to think that laptop may be throttling for heat or power being pushed that hard
an example of what im talking about is this - i have a 1070 and i would never try to run ultra, i also only use 1080p (so another possible issue may be some unusual resolution? your pics are 1639x1057?)
dx12 gave me a ‘slight’ boost in performance (possibly less microstutter when panning, little if any noticeable fps gain)
here is a comparison of my 1070 and your 3050 (yours is far right, with center being the desktop 3050)
https://www.videocardbenchmark.net/compare/GeForce-GTX-1070-vs-GeForce-RTX-3050-vs-GeForce-RTX-3050-Laptop-GPU/3521vs4495vs4408

i suggest going thru the gpu and windows power settings, many laptops throttle power for temps or when power draw becomes too much but i figure it may also just be the low vRam, vram is constantly moving data in and out (its used as a ‘swap space’), the less vram you have the more data must be moved to keep up with the game, this process of swapping data is what i think is bogging you down with dx12 - it just swaps more than dx11

EDIT:
if you click on the gpu name in the above link you can see that dx12 actually gives Less fps in benchmarks, so apparently the ‘improvements’ arent frames per second exactly, its better shaders i think (or goodnes forbid they exagerated the benifits of dx12 :P)
https://www.videocardbenchmark.net/gpu.php?gpu=GeForce+RTX+3050+Laptop+GPU&id=4408

2 Likes

Reduce the AMD FidelityFX back to 100% doesn’t make sense with your GPU. All other settings should be reduced as well if you want a fluid FPS. On my 2080 there is no difference between dx11 and dx12. Intested this in multiple scenerys in different contitions and time of day.

An update tonight. Some folks on VRFlight Sim Guy’s Discord were reporting better performance with HAGS on.

I tried it tonight and can confirm my ground stutter has gone with it enabled. It might be very system/hardware dependant so I’ll list my specs below.

10850k, 3090, 32 GB ram, 2TB Nvme
Windows 10
DirectX12, DLSS quality, render resolution in sim and OpenXR developer tools 100

Reverb G2 VR headset.