I have tried each stick of RAM and tested each slot to make sure there is not a problem with the sticks themselves or the ram slots. The PC will boot and work fine when i have two of the sticks in 1 and 3 or 2 and 4 however if i have 2 next to each other - 1 and 2 , 2 and 3 etc it will only use one stick. If I have sticks in all 4, The LEDs come on but the pc does not boot at all.
Specs:
Motherboard - ASRock 970 Pro3 R2.0
RAM - 4 x HyperX DDR3 1866 MHz 4gb
Specs:
Motherboard - ASRock 970 Pro3 R2.0
RAM - 4 x HyperX DDR3 1866 MHz 4gb