Direct X11 VS Direct X12

I have an RX6800 XT and using DX12 because performance is better than DX11. It’s really smooth. The annoying terrain bug is here but…

4 Likes

Can you enlighten me what’s this bug? I’m using DX12 and I haven’t noticed anything wrong with the terrain…

1 Like

It’s been ever-present in DX12 but appears totally at random. Basically, at some point of the games choosing (sometimes never, sometimes immediately) the incredibly low resolution bing textures start to bleed through a given airports custom ground textures and look pretty awful. Once they appear you can’t get rid of them unless you quit out of the game and restart.

It isn’t, and has never been, an issue in DX11. It’s taking Asobo a heck of a long time to fix it, which would suggest it’s a tricky so and so to track down.

7 Likes

Did they confirm it at any point?? Did they mention that they fix it? I haven’t heard or seen them speak about it once.

Pic taken with DX11

Pic taken with DX12:

And this is still quite harmless, it can look much worse.

9 Likes

Nope, you’re quite correct in this assessment. I don’t get why it’s so problematic nor why they seem to be making no headway in fixing this issue. They put a lot of work on DX12 for SU10, but if there have been any updates since, they haven’t done anything tangible. All reports of runaway VRAM usage during the beta were unacknowledged.

2 Likes
2 Likes

Thanks. Maybe I haven’t noticed because I almost exclusively fly addon airports.

it happens there, too. The thing is that not everyone gets these ground patterns, some systems are simply clear. First it was thought it would only happen to AMD systems but friends of mine with AMD/NVIDIA and INTEL/NVIDIA systems see it, too.

4 Likes

The Xbox version uses DX12.

…through, I believe, DX11 compatibility mode.

It’s not enough to enable Resizable bar in Bios. You have to enable it specific for MSFS 2020 through Nvidia Profile Inspector also. MSFS 2020 does not support Resizable bar, so you have to force it that way.

17.9 GB of VRAM for Intel A770 16 GB GPU.
i9-9900K, Z390 MB
4K HDR, TAA, DX12

Nice pic! I believe once the on board GPU Vram is used up it rolls over to a cache in RAM. At least it seems to be working well as once you go over the physical Vram allocation on Nvidia cards there is a good chance it starts to stutter.

Speaking of which what else are you running in the background as I see you’re using over 20gig of RAM. My RAM usage typically never goes over 15 gig while running the sim.

1 Like

Overcommited VRAM will tank performance, and a great example of what should be avoided when using DX12. If VRAM is an issue on DX12, some settings should be scaled back to fit within the available VRAM allocation.

The ARC 770 is far more capable of more than 18 fps at 1080p - even when paired with an older 9900k.

Notepad, Chrome Browser, and this FS2020 Forum usually.
That screenshot was at KEWR, Newark NJ, after landing on runway 22R.

Right now sitting on Runway 31R at KJFK, Kennedy NY, ready for takeoff.

Apps running:
Weather
Notepad
Word Doc
Excel Spreadsheet
MSI Afterburner
Chrome Browser, FS2020 Forum
FS2020

RAM = 24.0 GB (I have 64GB of RAM)
VRAM = 17.4

I noticed that MSI Afterburner showed 13.3 GB of RAM when FS2020 started loading.

i9-9900K, Z390 MB, 64GB RAM, DX12
Intel A770 16GB GPU

I fly 4K, TAA, HDR, DX12.
Flight is smooth.
Graphics are great.

If overcommitted, I can’t complain.
Don’t see it.
Don’t feel it.

There’s no if here - you are clearly overcommitted on the VRAM when using DX12. Turn down your terrain LOD to get your VRAM and performance under control, as you’re clearly pushing your system beyond what it can ideally handle. Most users would consider performance in the teens to be unacceptable - there’s no reason you can’t get double the performance by turning down a few settings.

Well, does Afterburner read VRAM allocation or VRAM usage? Two different things…

The default behavior should be VRAM usage, but can be verified from HWInfo. Regardless, allocated VRAM usage is typically around 500 MB higher than actual usage for MSFS based on my experience. If the current VRAM is 17.4 or 17.9 GB out of a 16 GB card, it’s clearly outside that range.

It is acceptable.
My T LoD is 4, O LoD is 9.

It doesn’t matter to me.
I don’t care about FPS or performance.

Graphics are great (detail and color).
Flight is responsive and smooth.

FS2020 is not a First Person Shooter.