I know what the framerate slider does -- it gives me NO MORE frames than what I have asked for and puts any extra energy into generating scenery.BUT -- what is it about the Sim that sometimes you can't get the frame rates that you ask for - it has to be the scenery at certain places surely? - is there any way we can say to the computer --don't give me any scenery until you can give me a frame rate of (say)15. Barry

Nut quite sure about this, but you could try turning some of the OTHER sliders down until you get consistently those (say) 15 and see what happens.Could be FS will start rendering more than asked for if it has the time.