Just curious ...

On Ubuntu I get a merely 25 fps doing the OpenGL example. If I move
the mouse it starts to get faster and reaches about 60 fps. Why? Now
on Windows7 running inside VirtualBox(!) on the very same hardware I
get up to 400 fps and there is no influence by moving the mouse. Are
there some magic buttons I have to press before using OpenGL on
Linux/Ubuntu?

Alex