I am running an ASUS PA329Q monitor at 3840 x 2160 resolution , using a NVIDEA GTX980 TI video card. Last night I upgraded from a clean install of windows 8 to 8.1. Ever since then my screen, icons, taskbar and windows have become huge. It virtually looks like the resolution is set at 800 x 600. I have all the latest updates installed and I simply cannot find the problem.