what is GTCS you ask? well it's a very well known feature in viewsonic monitors, lately I have heard more complains on viewsonic monitors than complements, after owning 3 GS790, in Optiquest Q95 & this PF77, the GTCS (Grainy Tint Color Shifts)have moved from my lower right corner to my lower left corner, on brown backgrounds, like the floor on monkey island 4, the grainy tint color would make that corner of the floor look purple, & now that it has shifted to the left corner, everyones icon here, isn't the right color anymore, people with a red face have a pink face instead, until i start scrolling their icon higher up the screen, any have grainy & tinted color problems & returned their monitor to end up with a better one? I have returned a monitor viewsonic once & the replacement wasn't even any better, it was like trading one problem for another.