First of all, I’m not a PC Hardware/ Software expert so bare with me and my explanation.
Please, don’t reply with negative comments before testing yourself, however I’m intressted if some of these solutions worked fore some of you.
What takes my interest is that I see many posts of users with the same or better hardware than me struggling with 10-20 fps gameplay.
Somehow I managed to run MSFS with a steady average of 40 fps in 4K resolution, I have no idea what setting solved the problem but it suddenly works. Just like a miracle.
Switched from HDMI to Display Port. (Important: Make sure its connected to the GPU and not MB! I’ve done that dumb mistake before)
Run the sim at the native resolution of your monitor, in my case 4K and use the render scale to lower it down to 1440p or 1080p if needed.
Use MSFS default graphic presets, in my case I chose “high-end” to start with and play around with the settings from there, one at a time until you are satisfied. This made a huge difference!, the only settings I’ve changed were clouds to ultra and AF to x16.
Many people just slide all of the settings to ultra and expect a smooth gameplay, not even dual 3090 can handle the pressure.
Not everybody has the option to upgrade their CPU but if you can it’ll make a huge difference, as long I can remember back to fs2004 and FSX, the sims have always been CPU heavy.
I began my journey in MSFS 2020 with i7 6700k 4.0Ghz.and GTX 1070 TURBO, it runned fine but not really where I wanted it to be, therefore I upgraded to a newer GPU, the 3070.
Performance got better but not as I expected, it turned out my CPU was bottlenecking the GPU by not keeping up with it. The big change came when I upgraded to a newer i9 10900K and here is where the big change came, now It runs like a dream!
Let me know if this works for you!