Question PC reading only 1 stick of ram

[Intel's still got it]

Just built my first PC. When I booted I checked my specs and its reading 8gb of ram when I have 16gb (8x2) I launched using both sticks in each dimm slot (my mobo has 2) and nothing has changed

 

[rgd1101]

full system spec? exact model of the ram?

try 1 stick at a time in both slot to see if the issue with the ram or the slot?

 

[Intel's still got it]

full system spec? exact model of the ram?

try 1 stick at a time in both slot to see if the issue with the ram or the slot?

I5-6600k
GTX 1060 6gb
EVGA 500w PSU
Gigabyte GA-110M-M.2 LGA 1151
Ballistix Sport ddr4 2666 Mt/s PC4-21300 (8gbx2)
NZXT S340
WD 1tb hard drive
120gb SSD

Already tried each stick in each slot

 

[rgd1101]

Already tried each stick in each slot

and the result?