Trying to urgrade the RAM, currently has 4GB installed (2 - 2GB sticks), want to do video editing. I have researched it, and the motherboard, QK401US#ABA, is supposed to support 16GB DDR3 1333. The first ones I purchased (2 - 8GB sticks) had a much higher clock speed, and I got the five beep flashing red light. I returned them for a set that was supposed to be compatible with a 1333 speed, same thing. I bought a third set, 8GB DDR3 1333, still a five beep flashing red light. What am I doing wrong? Do I need four sticks of 4 GB? It still runs fine with the original RAM.