Pulling this out of the hotfix thread...so I've always run MSFS with Hyperthreading on, early on I found it greatly reduced stutters.  Reading about others having better performance with HT off I gave it a try.  I was watching FPS using both the steam overlay (I turned this on just for this test) and the Ctrl-Z mod.

Flying out of ORBX KORS in the amphibious C172 with HT on I was getting roughly 57-59 according to the Steam counter, and 45-47 according to the Ctrl-Z mod counter.

With HT off the Steam counter didn't change much (maybe up by 1-2 FPS generally?) but the Ctrl-Z counter dropped to high 30's.

Now I'm just confused haha.  Both seemed quite smooth and not that different so I'm inclined to trust the steam FPS counter over Ctrl-Z.  If steam is the one to believe I have no real difference between HT on or off so I guess probably better to leave it off and reduce CPU heat?  I do wonder what the difference is between the two FPS counters, and if I'm somehow gaining something with HT on that the Ctrl-Z counter is picking up that the steam one is not?  I wonder how their values could be so different.

Edited July 30, 20214 yr by regis9

My performance is so good right now that I have shifted from optimizing FPS to mitigating heat. I actually under-clocked my CPU to 4.5 GHz and I still get 70 to 80 FPS but with 10 C lower CPU temps. Everything on Ultra. 

HT  ON    end of story 🙂 

What does the Dev Mode FPS display show?  I'd trust that over a mod.  I'm assuming it's been updated since Tuesday but if not, I do remember some comments about it having issues after the patch.  Not really sure why people are turning HT off unless they're getting reduced performance due to extra heat causing the CPU to downclock.  This isn't FSX on WinXP/Win7 with CPU masks and stuff added to the config file.  An updated current Win10 and FS2020 should not be needing hacks like that.  It's also possible that Asobo did something dumb like read the CPU type and refer to some internal lookup on how many threads it's supposed to have available (in your case, 20) and is trying to set up its multithreading based on that, but since 1/2 of the logical cores are turned off without HT it causes an issue.  However, while I do Java stuff for work, I've never explicitly done games dev or development of multi-threaded apps so I'm not familiar with how that stuff does or does not work.