I have an Asus Sabertooth Z87 motherboard with 2x8gb sticks of Kingston Hyper X ram. When i turn on my computer the ram led lights on the motherboard turns on and it fails post then restarts and stays started up with the ram lights still on. At this point my monitor is black screen the whole time. I then put the ram into my friends computer and he put his ram (2x4gb Corsair vengence) into mine, and both computers start normally and work fine. My computer isnt new and has never had this problem before. This happened after we tried SLI'ing our 770's together and we put my ram and my 770 into his computer.