DIMM_B2 and DIMM_A1 are the only slots that work. Help

[am171945sub1]

Hello, i've recently purchased and upgrade my CPU and Motherboard, everything seems to work fine however my DDR4 ram modules only seem to work in 2/4 of the slots on my motherboard. Slots B2 and A1 function just fine, however B1 and A2 don't work at all.

Motherboard : Asus prime Z370-a
CPU : i7-8700k
RAM : Corsair Veangence 2x8GB 2400Mhz

 

[kanewolf]

Bent CPU pins would be one possible reason.