Got the game on Steam 4 days ago and have been playing it on my new desktop PC with the following specs:
Windows 10 Home
Intel 9th Generation i7-9700F 3.0 GHZ 8 Core Processor with 4.7 GHZ Turbo Boost
Nvidia Geforce GTX 1660 TI 6 GB Ram
16 GB Ram
240 GB SSD
I have been running the game on all Ultra Settings with only Motion Blur and Sunshafts off and at 4K resolution. With these settings my FPS alternates between 58 and 60 FPS, getting 60 FPS probably 99% of the time. At least it did until this morning. After launching the game today I now get 22-25 FPS on the same settings. To get back to 60 FPS on Ultra settings I now have to set the resolution to 1080P, and even then it drops to the mid 30s occasionally, which it never did before this morning. There were absolutely no changes made to the in-game settings or, to the best of my knowledge, any PC settings between my last session where I was getting a steady 60 FPS on Ultra settings at 4K resolution and this morning when it's dropped to 22-25 FPS on the same settings. There were also no updates to Windows, any drivers or any other windows programs during that time frame either. I've spent hours researching this and I'm completely stumped.
Other pertinent info:
The problem occurs in all save games created prior to the drop and any new game on random gen, pregens or Navezgane created after the drop.
Validating Steam files didn't help.
I've attached 2 output logs to this post. One from the last day I was getting 60 FPS(6-20) and the next day when I randomly dropped to approximately 25 FPS for seemingly no reason (6-21.)
output_log__2020-06-20__18-32-12 - Copy.txt
output_log__2020-06-21__14-00-08 - Copy.txt