When freshly restarted, (the game, not the PC) I get 150-200 FPS, and then it steadily drops. about 100 on the second game, 50 on the third. After that It collapses, with about 1-2 second long pauses. It gets unplayable before that point, off course.
This is how it looks:
This happens every time in the game, 100%, no problem reproducing it. If, like, someone is interested in fixing this. I can force a full dump from Process Explorer and upload it, should be easy to debug.
This is on I7 4770, 32GB RAM, SSD, Windows 10, latest drivers, 750 Ti, 2 GB.
There is 20+ GB free ram, GPU monitoring shows 1 GB gpu ram free. There is no disk activity. Processor shows 15-25% usage, so about 2 cores, out of 8.