Big Fps drop SU6 LOD200-400 CPU Hit

It’s a 1080p monitor.

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Hi,

So you are running a RTX3070 with a 1080p monitor?

That’s practically the same as putting a ferrari engine in a fiat 500.

A graphics card like that would be more happy with a higher resolution to stretch its legs.
But regardless of this you should be able to play with a descent framerate!! But you you have to configure the settings correctly.

For the best experience i recommend playing around with the settings.
And watch this video closely!!

Let me know if this has helped you.

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Thanks, will give that a watch.

Yeah and monitor is not HDR.

So I think soon I will get a 1440p HDR monitor.

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Before SU6 I had Terrain LOD at 400 (via cfg) with smooth 60fps in flight (ultra, 1440p). since SU6 my FPS has dropped 20 and, even worse, there are heavy stutters when changing views or camera angles.

If I drop the LOD down to 200 everything is back to smooth sailing, however now the terrain looks much, much worse. especially the distant mesh: mountains become smooth, lumpy messes.

This is very frustrating, as from my end I now have to have a tradeoff between smoothness or beautiful mountains, where before SU6 there was no tradeoff and both were achievable.

Has this been the case with anyone else described as I’ve experienced it?

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I suspect the limiting factor for setting LOD to 400 is single-core speed. DX11 rendering pipeline uses a single main thread with a few secondary threads handling other tasks. You can be in a situation where the main thread is saturated at 100% (hence the message “Limited by main thread”) creating a CPU bottleneck. In this type of scenario, high single-core speed makes a significant difference in performance. Current processors with high single-core boosting approaching 5 Ghz, like the high-end Ryzen 5000s and the 11700k/11900k, will probably handle LOD at 400 relatively easy. The move to DX12 will move away from that singe main thread and spread out the load across multiple cores. I suspect this will help most users limited by low single core speed.

Personally, there’s a minimal performance hit of about 3-4 FPS on my rig setting LOD to 400 vs 200. I have a 5950x boosting up 5 Ghz, which might be the helping factor here.

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Please let me know if this video helped you better optimize the settings.

I can confirm that my 5ghz i7 10700K is not at it’s limits with lod 400 (all cores are under heavy load, but none exceeds 60% usage), but the game still extremely suffers from fps drops (about halfing the fps compared to lod200 in SU5).
Really hope dx12 tackles this issue

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MODERATOR EDIT:
My PC is amd 3600x CPU, 32 gigs of Ram at 3200 and RTX3080 SSD hard drive and 32 inch 4k monitor. With this update with everything in Ultra in 4K and LOD 200 by default, locked the VSINC to 30 fps runs perfectly and smoothly. The GPU works less forced maximum at 80%. If I lock the VSINC at 60 fps the GPU works between 90 and 100% constantly. I think the solution at the moment is to lock the VSINC at 30 fps and not obsess over reaching 60 fps.

Mi PC es CPU amd 3600x, 32 gigas de Ram a 3200 y RTX3080 disco duro SSD y monitor de 32 pulgadas 4k. Con esta actualización con todo en Ultra en 4K y LOD 200 por defecto, bloqueado el VSINC a 30 fps corre perfectamente y fluido. La GPU trabaja menos forzada máximo al 80%. Si bloqueo la VSINC a 60 fps la GPU trabaja entre el 90 y 100% de forma constante. Creo que la solución por el momento es bloquear la VSINC a 30 fps y no obsesionarse en alcanzar los 60 fps.

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I have a 10900k w RTX3090 and are experiencing severe fps drops w/ lod 400 after su6

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I checked the builtin frame counter today and it says 99% of times “limited by mainthread”, which confirms my assumption that its neither my CPU, nor my GPU which is bottlenecking, but the game itself.

Yeah i have noticed this too, I seem to be constantly limited by mainthread.

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Out of curiosity - what is your VRAM usage with LOD 400? You may be hitting the limit which is creating latency between the CPU/GPU.

Good point, I might recheck this, but it was between 6-7Gb (on a RTX3070 in WQHD) if i recall correctly. Yet it wouldn’t cause a mainthread bottleneck, but GPU/CPU or not?

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A question for experts! Should we again “disable windows optimization for fullscreen” (msfs exe file) and turn “Threated optimization” OFF in nvidia panel for MSFS ? Thanks in advance.
(i9-9900k/asus rtx tuf 3080/ 32 ram/windows 10 home)

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the “mainthread” runs on your CPU, so it IS a CPU limit; specifically; the single threaded speed of your CPU. Might be that the main thread hops between 2 cores on your CPU faster than your monitoring software can register (most of those poll every second or something like that).

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For an Intel 10900k should I have hyperthreading on or off? Has anyone done a benchmark with ht on and off to share results? Thanks a lot!

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SIM runs like butter in my system with LOD 400. I have a 5900x and an RTX 3080. But I have seen people with similar specs crying about performance. You people must have wrecked your cfgs with unnecessary tweaks for such garbage performance. SU6 has been THE best update yet for me.

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then don’t do that!!!

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The mainthread usually IS a CPU limit…

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Hi I have HT turned off via Process Lasso,
I don’t have any empirical evidence unfortunately, but it does feel smoother

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