Asrock z97 extreme6 ram problems never seen before

Hi, I have ram issue with my z97 extreme6 mobo... If I try to put 1 ram stick in my pc won't boot gets error 55 so I put 2 sticks in of the same size and type etc and the pc boots but won't show more than 1 stick as if the other slot is empty I put them in the correct slots a1 b1, a2 b2 also if I put a single stick of 8gb ram it will not work but if I put the 8gb stick and a 4gb stick in it will move only register the slot with 4gb in not the 8 I currently use a i5 processor normal har drive I have installed another cpu the same as my original one with no change and tried numerous different ram sticks I have checked the cpu slot for bent pins and it looks brand new in there checking with a magnifying glass I could also send pictures of the cpu slot I also know the exact pin which would be damaged if there was one all pins exactly the same height and in correct alignment to the others I have never came across this in my life if anyone could help me at all thanks for you time