that happens too but what I'm talking about here is that my main window drops way under the min fps - basically its like wow in that window gets hosed - strangely switching to an alt; that window is fine (can even go back to max fps) but getting it back as main and it drops to a few fps/horrible lag... it's really irritating as it happens about every few switches between my 5th and my main (shift-f5)

edit: at the moment it happens 100% of the time I switch to my 5th window :-( and I have to exit everything and restart everything to recover - extremely painful :-(