I recently purchased a full system from ocuk including 22" monitor, but i still have an old 19" monitor left over, so i thought why not use it as a second monitor, but i need to know, when i'm playing graphically intense games like crysis, will just turning the 19" monitor off stop any graphics going to it (crysis on a 22" screen + a 19" screen will be low fps) or will i have to unplug it at the back and change the settings back to single screen to play crysis, if that makes sense 

pc is packed up according to the emails and should arrive Friday