not again that myth that msfs use only 4 cores…

If it uses more i stand corrected, i was only quoting what i had seen in tests. :slight_smile:

1 Like

It’s cpu limited because you can’t always parallelize logic based calculations which depends on some previous result or modifies some common data in memory. Those sequential operations needs to happen on a single core. If they are forcefully spread over multiple cores, the game will perform even worse because of thread synchronisation. That’s why MSFS tries to use as many cores as it can. But only one or two of those cores runs the most intense sequential operations. And those cause the bottleneck. Even if MSFS uses 16 cores, if those sequential operations cannot be parallelized, then those one or two core will be always fully utilised but the rest of the 14 cores will wait for those to cores to complete certain tasks and remain underutilized. Now if we try to run this on a quad core system, then we may see all 4 cores being fully utilised because those calculations which were spread over the 14 cores in the previous example will run on only 2 cores in this example. And that’s why they will have more utilisation.

Apologies for the programming lecture.


Is you case big enough and have sufficient fnags to get the heat of of the case. On my current build, I originally had bought a case that was too small and things were getting hot.

I changed the case and it made a huge difference. I have six fans. Three in front with the radiator AIO cooler for the CPU. Those three are intake fans. I have two fan on top and one in the back whihc are exhausts.

I have a 3080Ti and my monitor is inly 1140p 60hz, so on average I only run at about 50% on the GPU and CPU and my GPU is usually about 72C.

Make sure your are are clean and that you are getting good air circulation through the case. And as other have mentioned, make sure your fan curve cools things down before they get too hot.

With the water cooler I have, it goes by the temperature of the water. By the time the water hits 40C, the fans are cranking pretty good. If you have a AIO, make sure that you fan speed are based off the water and tot the CPU. If you go by the CPU temps, the water will already be too hot and hard to cool down.

And like I said, make sure you same enough air flowing through your case. A hot case will heat everything up.

Very interesting, thanks

Here are some possible solutions for those with overheating problems in addition to the hints offered above. I’ll use my current setup as the example. 12900kf/3080ti/5120x1440/Ultra settings/200TLOD. Oh, and I have it running in an Alienware case…famous for their cooling :rofl:

DX11/TAA/no frame limit/30-60 FPS range. GPU will be used 90-100%. GPU temp will climb to 81-82C, close the the set limit. Memory and hotspot will climb to low 90’s. GPU is pulling pretty much it’s design 350w. These temps are all within limits, but higher than I like them.

DX11/TAA/40 FPS limit/ 40 FPS most of the time. GPU usage down to the high 70’s. GPU temp drops into the 70’s. Memory and hot spot down to the 80’s. GPU usage drops into the 70% range. GPU power draw reduced by 30-50w. Much more to my liking.

DX11/DLSS/40FPS limit. GPU usage drops down into the 40-50% range. GPU temp drops to low 70’s, hotspot low 80’s, power draw up to 100w less!

CPU continues to show the same usage and temps regardless of the above settings.

Anyway…perhaps some settings to try if you’re running a little “warm”. Probably somewhat different on different machines but might help if you’re in a bind.

All data from GPU-Z.

I second this.

I was seeing temps of approximately 85 degrees running MSFS. This week I started undervolting my Nvidia card (it will not damage it, no worries, there’s good stuff on youtube to check out if you want to try).

My card now runs on 750 volts, keeping the temperatures around 55 degrees and my frame rates went up by about 20 to 25% too, now the card has a lot more thermal space. Using MSI Afterburner, you just make an MSFS-dedicated profile that you can turn on and off so undervolting your card isn’t diffucult or permanent.

I followed exactly what this person was demonstrating and I’m very glad doing so.


These posts makes me love my 3080OC (LHR) even more, it’s one limiting factor is it’s maximum voltage.

It’s pretty much crank up the clocks until it crashes and that’s it without a shunt mod.

Which settings would you recommend turning down from ULTRA that have very little visible change?

I can only go on what i have seen myself - there are too many combinations, but the ones i’ll keep on medium or high include these, if i go into VR, many of these will be turned off.

Off Screen Terrain Pre-caching>
Terrain Vector Data >
Buildings >
Trees >
Grass/Bushes >
Texture Resolution >
Texture Supersampling >
Texture Synthesis >
Water Waves >
Shadow Maps >
Terrain Shadows >
Contact Shadows >
Windshield Effects >
Ambient Occlusion >
Cubemap Reflections >
Raymarched Reflections >
Light Shafts >
Bloom >
Depth of Field >
Motion Blur >
Lens Correction >
Lens Flare >
Glass Cockpit Refresh Rate>

As far as i can tell, the heavy-hitters are.
Texture resolution
Texture synthesis
Texture supersampling
Off-screen terrain pre-caching
Terrain LOD
Render scaling
Ambient occlusion

I stand to be corrected on any of these points though :wink:

and bit more exact, is the DX11 the limiting factor… but there are so many situations where we are not limited by the DX11 main thread problem and we can see the cpu run in 100% utilization.
And if we come back to the topic “Overtemp” , will that mean that the system is in future more utilized and more heat is produced. We had allready in Su10 beta the first reports where users “report as a bug” ( lol ) that the system now use more of the cpu and the temps are increased ( my answer was, that I was lucky about because it means the devs do a good job ).

@DaveJK9173 may be you check the wrong tests :sweat_smile:

1 Like

Well, i can agree it makes hardware run hot. But that means it uses all of the hardware we have right? To me that is good performance. Reducing settings only will not decrease temp. Reducing settings will make the sim run at higher fps with same usage of hardware. To decrease temp you need to limit fps and settings or underclock hardware.


OK, I have solved the problem and I share it in case there are more people in the same situation.
I thank everyone who commented, by the way I answer a couple of things here.
As I said, it is not a cabinet or ventilation or maintenance problem.
Nor is it a matter of lowering the quality, because I used the same simulator and the same configuration with smaller boards, and even with less FPS I had everything in ultra without overheating.

There are people that I see have other models of video cards, not the MSI RX 6700XT Gaming 12G that is mine. I have mentioned that it is the “hottest” board in the 6700 series so far, you can see that in lab tests on various sites on the net. Which I trust.
The RTX 3080 is more powerful than the 6700XT and also the temperature limit is relatively low (80 degrees) compared to the 6700 (110 degrees), after that it does thermal throttling. They are not comparable, they are almost 30 degrees difference in the hotspot.

After doing many tests, because I didn’t want to lose the ULTRA quality and I didn’t want to harm the video card either, I removed the factory settings and started reducing the voltage while also limiting the speed. What the 6700 has is a high performance for its segment based on energy bursts that are sometimes a bit scary when you see the jumps it makes.
The undervolting worked wonders, I’m having hotspot temperatures below 100 degrees (usually 85/95) and sustained temperatures of 60/70 degrees, more than acceptable for the requirements of the game.
I made up for the difference with a bit of an overclock to the VRAM and so far everything works great.
This has always been a “hot” video card, but something has changed in the latest updates since the configuration was by default in the AMD Adrenalin Software panel and it may be due to the simulator or the drivers (updated to the latest version), but the point is that there was a worrying problem that is finally solvedand FPS not drop of 29/30.
Thanks again for your interest and greetings to all.

1 Like

Ah but tests from when? … SU5 and SU6 changed a lot and now we have DX12 all bets are off as to just how many cores are used. Yes MSFS and Windows can run on just 8 threads however I daresay that means some paging into VM and therefore it is not optimal. Then of course there’s other apps like AIG, Navigraph, OBS etc. all take up at least one thread at some stage.

1 Like

I don’t know the inner workings of FS, each update is a mystery and a lottery because nobody knows who may have a problem.
DX12 has not given me better results than DX11, not at least in what is visible on the screen and it is not a higher amount of FPS. I did not have any improvements with V-Sync either, quite the opposite in my case, and finally I do not need to use the FPS limiter because it does not go much more than 30 or 40 at the most (despite the fact that the AMD program mentions that FS2020 has a “marginal” performance with 52FPS when logging, 52 FPS that I have never seen in operation.
As I said, this has to do with a temperature problem, I don’t know if it was in the last update or the previous one since I hadn’t been using the Sim much and I didn’t look at the temperature either, I only paid attention to that when I felt excessive heat on the tempered glass side of the cabinet even though the coolers were running at high speed.
In short, in these last days that I was carrying out tests, I accumulated more than 17 hours of flight and the temperature is maintained. Undervolting and VRAM throttling have worked well for me.

I never actually looked at the hot spot but … stay out of my PC you :smiley:

Sitting idle at Heathrow #9

Memory temperature 82.0° !! … I suggest you depart Heathrow sharpish! :grin:

Hi Salem 978. See the link above and suffer.

Each plate has some strong point and some weak point. My concern about the hotspot is not in vain because in these last 40 or 50 years that I have worked in the technology industry I know very well that “the thread is cut at the thinnest part”.
Who knows how a fuse works, knows what temperature does to physical materials (in the case of the fuse, which is a metallic thread, it melts it at the weakest point).
As I said before, except for vacuum tubes (used many years ago) that had a heater to keep them hot and achieve optimum performance, semiconductors must be kept away from high temperatures, there is a process called “thermal acceleration” (I don’t know if there is an exact translation in English for “embalaje térmico”) where more generated heat, the semiconductor becomes “more conductive”, passes more current, generates more heat because it dissipates more power and this becomes a vicious circle until it reaches the damage or destruction of the material. Video cards, processors and chipsets are the most problematic. Few people do maintenance - and gamers should do it AT LEAST once a year - removing old thermal paste and thermal pads and replacing them with new ones. Clean the entire interior with an air compressor (1Kg of pressure or 2 is more than enough) and keep the cables organized inside to improve air circulation. I’ve been servicing PCs for many, many years and I’ve seen a lot of damaged equipment/components for that reason.
I will stay away from your team…unless you come to visit my country :rofl:
Greetings from the South of Argentina.