So I guess I'm not the only one having it. Josiah, if you set fps_max in your script (in the main function) to 200, 60, and 1000 in your empty level, what is your frame rate? In my case, I get 64, 32, and ~270 for these. My experimental level, at it's simplest, is nothing more than a single 64x16x16 block (or something like that, but not hollowed out) with the default texture assigned to it.

When I first installed XP Pro, everything was normal and I was using 6.31.4. As soon as I installed the 6.40.4 (or 6.40.2?) update, the frame rate seemed to always snap at some power of 2 which makes it very difficult to fix and get back to normal. I once reported this as a bug, but as it seems, others are getting it as well. I tried the d3d_triplebuffer thing and it didn't work. I tried going into the display settings to turn on vsync and that didn't work no matter how I did it.

I'm trying to get it so that my 2D game run exactly on 60 frames per second in both windowed and fullscreen modes. At the 64 fps I'm getting, it plays back faster than it should and it causes both of the logos (the Gamestudio logo and my own logo) come up and disappear in under a second at 270 fps. Also, because the frame rate is not in sync with the monitor, the motion is somewhat jerky (as if watching a video and 1 frame was being skipped after 19 normal frames (like having the frame displayed go something like 17, 18, 19, 21, 22, 23, ..., 38, 39, 40, 42, 43, 44, and so on where frame 20, 41, 62, etc. are not displayed at all).

I only use windowed mode for testing, except if the test involves going to fullscreen to test if the function works (and to fix the bugs if there are any).