Okay, I tried disabling it (choosing "always off") like you said. With the same conditions as shown in the screenshots given, I'm getting the exact same symptoms - the frame rate locks to a power of 2. For the fun of it, I tried "always on" and even that has no effect so it has to be something else.... The weird thing about it is that, when I have fps_max at 60 and fps_min at 10, the frame rate doesn't get much past 40, no where near 60. I set fps_max at 62 and fps_min at 60 and I was getting from 40 to 48 fps which is really weird. I first though it was an issue with 6.40.2, but I'm also getting this with 6.31.4 as well.... Weird....