I have G.Skill Ripjaws X 4x4GB (F3-12800CL9Q-16GBXL) Memory running at 1600 MHz. All sticks have been tested and work fine. The computer runs fine when only using 2 sticks but only 2 sticks. Three sticks = constant BSOD (no surprise, ASUS reccomends using 1,2, or 4 sticks). Four Sticks = no boot whatsoever. DRAM light stays on continuously and pressing it to go through tunes does nothing.