i've had this problem for a while now and have searched high and low for a solution with no joy. occasionally on start up my screens refresh rate looks off so i bring up the graphics settings by right clicking screen etc,but when you get into where the refresh rate settings are (advanced,adapter,refresh rate) the place where it usually reads optimal or whatever, has disappeared. i restart pc and its back? i've re-installed the graphics card,updated drivers,re-installed drivers,changed graphics card run all sorts of virus stuff and used reg.mechanic. the only thing i can think off now is that its the monitor but this should'nt effect graphics/software should it. any ideas anyone much appreciated.