This happened to me oddly enough, I followed Blackdogs post to the letter, I hadn't got any mods installed i just wanted to clean up the patches and do a fresh start, but I noticed a considerable drop in FPS (using black death track) and more stuttering. Ive not found a fix yet. :(

oh sh...
that sounds not good for me!

Take a look, which core uses the game the little. From the others switch the TrackIR process off. Maybe it helps.

OK and how do i do that??i would need a step by step instruction.

Open the task manager (right click on tray)
Click on the process tab (You see the processor usage on the performance page)
Search the TrackIR .exe
right click, affinity settings
remove the markings
click ok


It doesn't working, if you run the program "as administrator", and have to repeat this at every program restart (there is a program possibly, with which this can be automated, I was not searching yet)

thx cheesehawk for the detailed explanation and the patience!
to tom:thx for the tip,but it didnt make a difference.