Well I’m not sure exactly what I did to fix the issue but I’ve managed to mitigate my stutters finally. They are not 100% gone but, completely reduced to almost nothing. Within acceptable range and what everyone probably deals with. The stutter is way less frequent and it’s not even really a stutter anymore, just a single frame skip when large chunks of terrain load in. Basically unnoticeable unless you are looking for it. A part of me is skeptical though since I don’t feel like I did anything meaningful but yeah, they are gone.
The thing that seems to have fixed it is undervolting my CPU. I am just using PBO, but I also applied a negative voltage offset to my CPU + Level 3 LLC and tried my best to keep it at around 1.35v or less at sustained max loads. Before it would reach around 1.4v which is ‘normal’ for AMD but still pretty high.
My benchmarks haven’t changed, if anything they actually improved a tiny bit and my CPU temperatures are noticeably cooler too. This was all around worth it, however I am not entirely sure why the game is fixed because of this. I had no issues with anything else on my system, even arguably much more latency-sensitive stuff like my audio interface running at 1ms sample rates etc. And nothing else about my system would hang while MSFS did.
For anyone who needs the specifics of what I did, I have an ASUS X570 Prime Pro and a AMD Ryzen 5950X. I set PBO on in the BIOS and then applied a negative voltage of 0.15v to the CPU, along with Level 3 Load Line Calibration to the CPU. I left the socket settings on auto for both voltage and LLC.
I would also recommend not using rolling cache or anything like that. Finally I can enjoy the game, thanks again.
I had also reset my BIOS to optimised defaults like I mentioned before and doing that didn’t fix the issue. But yeah, I’m just glad it’s okay, for now anyway. I just hope this was actually the fix for me and it’s not just luck that it’s working completely fine right now lol. Thank you very much for your help and suggestions, it got me on the right path to getting this fixed and I appreciate it!