I have an another issue that sometimes my cpu stucks at 100% and ‘Limited by main thread’ giving 15 fps in same places that I’ve been flying at 50fps. The only fix is restarting the game, and 50fps again. And try restarting the game again and cpu uses 100% for example. My point is it is totally random, restarting might fix might not fix. I have a 6600k, it is not great for this game, but the only thing I know is it is capable of that 50 fps, and definitely something is going on with the game itself.
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As somebody already said, I think we should focus our hopes towards the Citation Longitude. At the moment it’s the only plane with glass cockpit and a complex set of instruments that runs butter smooth (better than the Cessna with G1000 on my system).
As somebody deduced, it’s probably one of the latest planes developed in the pipeline and they found a decent solution for the glass cockpit data-feeding and rendering. This means they already have a “cure” and it’s just a matter of time and patches to fix all the other planes.
Fingers crossed 
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I did, exactly, if they managed to make it work in the Citation they can optimize the rest of the planes at a later date, we will probably just have to wait and let them know through zendesk in case they have not noticed for some reason 
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I’m running a 8700K with a 1080TI. I spent a good amount of time experimenting with different quality levels and resolutions. 4K is obviously out of the question with my HW. However 1080p and 1440p on Ultra never max out the GPU. I therefore overclocked the 8700K to 5.1GHz and disabled hyper threading with very good results. The stuttering became a very rare occurrence and the game is butter smooth. Still not maxing out the GPU, but very close.
If your game is CPU bound, overclocking it is probably the best move right now.
IT actually doesn’t mean the CPU can’t handle it, it means the threading in the program is dropping data related to the CPU. But even when the FPS checker in the game is in the perfect green, it still says that.
I have an I( also and with twice the threads of a I7 and the way the CPU is set up it will disperse more evenly and not be utilized fully.
They will patch it. Give it time. When they move towards the Direct X 12 update and optimizations then we can breath. Except in airbus and 747 cockpits im at a locked 60 fps (technically shows 60.1) on ultra settings. at the proper render resolution to desktop. 4k will drop it however much lower then it was in Alpha and beta. If you run Nvidia SK DEV kit to much junk is left behind in the gpu memory, even after closing to menu. The fact the hanger is fully rendered in the background when setting flight plans, is ridiculous.
The Games dev reports are not accurate at this moment, certain items are not reported that are rendered. THE actual Nvidia reports are different, and memory usage is different.
I stream in 4k at the same time in these flights. Still never full pushed the CPU. THE gu isn’t actually fully pushed except in some render points, especially the cockpits of the airliners.
They need to optimize those, remove unneeded rendered buttons of inop buttons and have options for cockpit versions. and optimize it all together.
They have optimizations to do… we will have to be patient.
Over clocking the CPU won’t do anything.
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So my theory applies, until the cockpit displays are optimized to call more render threads and just not main thread, then utilization will improve over multiple threads pysical and logical cores. Right now FPS drops over 50% inside the 787 cockpit. GPU Util. drops to nill sub 10% CPU Util drops to sub 50% and you have a limited by main thread. Out side cockpit the sim engine utilizes all the resources.and you get good FPS.
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in theory…
I am hoping. It jsut needs to be, beta wasnt as bad for some reason
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This is not how CPU performance works at all. Clockspeed can only be used to compare similarly performing processors. For instance, a single thread of a 10700k running a 4.0GHz (yes I know that would be slow) will perform SIGNIFICANTLY faster than a single thread of a Pentium 4 clocked at 4.0GHz. Instructions Per Cycle and how the actual architecture works, including things like cache and the like are more important to be optimized than having an extremely high clockspeed. For instance, the first Generation of Ryzen chips had much slower clockspeeds than the last generation of AMD chips such as Bulldozer, and yet single threaded performance blew Bulldozer completely out of the water.
And the reason that the CPU shows up as not being used is because the game can only be so multi-threaded. Sure, you can get multiple threads processing different things like clouds, weather effects, the flight modeling, displays and such, but they always end up having to wait on some other thread somewhere, its pointless to update your G1000 twice in the time that it takes to draw the entire frame in the first place, that would be a waste of power. Similarly, if one of your CPU cores is able to process three hundred frames worth of flight model calculations, it would bog down the main thread of the sim if it tried feeding in flight model calculations that were happening 5x faster than your GPU could actually output render frames. And then if its processed flight model updates for the next 1.5 seconds of flight, but at 0.3 seconds in you slightly adjust your pressure on the yolk it now has to toss out all those rendered frames, energy spent and heat generated to start calculating completely new calculations.
Unfortunately, games just don’t multithread anywhere near as well as things like video rendering applications. Now, that doesn’t mean that there isn’t room to improve. Hell, I’m sure there’s plenty of room to improve and bugs to be fixed that could greatly improve performance across the board for everyone. But no, we’re never going to see 100% CPU usage across all threads unless Asobo just intentionally programs it to use all spare processing power to calculate prime numbers in the background to turn your PC into a space heater.
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I think you’re right on this one. The airliners displays seem extremely unoptimized. When one of the GA planes that has 3 full Garmin displays in it (I can’t remember if its G1000s or G3000s) shows a difference of about 5 FPS between internal and external views I get the feeling that the much more simple to render airliner displays are just buggy. Hell, I just tried out starting up an A320 in KLGA and it was pretty amusing. Completely cold and dark the FPS difference between being inside and outside the plane was about 5 whole FPS, but after powering up I lost at least 10 more fps, and then after loading in a simple, short flight plan I lost probably another 10 fps.
I can confirm, the bushplane gives me much better FPS compared to say the Extra which has two MFDs (displays).
Same issue here.
I7-7700K 4.4 GHz
GTX 1080
16GB RAM
2K screen
https://forums.flightsimulator.com/t/a320-cockpit-low-gpu-usage/213312?u=stellarrunner
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Same here 
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Ya from what my buddy said the displays are only using the main thread to call to render. Because the way it renders it only uses one. And currently can’t use more. Some things that need to render are sent to the GPU to cache and when called later boom done. That is cached during like loading the simulator. Apparently none of these particular displays are pre-cached and are sent real time to be rendered on one thread. The main one.
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I have the same issue. In fact in the 787 you can watch the coherent gtdraw latency slowly creep up as you power the plane on and start entering a flight plan. I got it up to 40ms with a transatlantic flightplan. I don’t know about the sim but in other realms 20ms latency is enough to notice issues.
787 is unplayable for me, I get 55 fps outside 14 inside.
Turning off V- sync somehow works for me. FPS increases from 20 to 40
Same here, CPU use only 40 %
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Brendan Gregg proposes the USE method (http://www.brendangregg.com/usemethod.html). Which basically says Utilization Saturation Errors.
If you have performance problems, what is the utilization? When it’s not 100%, you still might have kind of saturation because the CPU could do more but needs to wait for something like resources being loaded, synchronization etc. So that leads to the run queue being filled up and therefore you have saturation…
This is my hope that the Team will be able to optimize, e.g. to improve synchronization or whatever happens that leads to this saturation.
Out of curiosity, is any of you using any manual technique or specific software to kill all the useless services and processes in W10 not needed for FS2020 and gaming in general?
I’m not using an “special” software for that purpose.
Regarding overclocking, I’m using Game Boost and XMP of my motherboard and also let run the analyzer of MSI Afterburner and use that profile.
Today I’ve tried to increase my RAM speed a little resulting in a few frames more (DDR4 2666 16-18-18-35 to DDR4 2800 15-17-17-37). Let’s see if it runs stable over longer time.
From the version we now have, it seems to me that having an 8 core CPU and 32 GB of really fast RAM is most important for performance.
I’ve just checked: the improvement of RAM speed brings in my case 2 fps more in the KJFK scenario with the A320.
I also played around with the process affinity and in the A320 KJFK scenario if does almost not matter if a assign it all cores or only 8. With cores 0-7 I get ~ 33 and with all cores ~ 35 up to 36.
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