Asrock Extreme4 z77 not utilizing 4 sticks of ram.

[Shemegory]

I posted about a similar problem but I was using mis-matched RAM (corsair and g.skill), since changed to the same model but the problem persists

since changed to the same model but the problem persists, Motherboard and cpu-z recognize the ram

 

Found more or less the same problem googling (http://www.tomshardware.com/answers/id-2074084/asrock-extreme3-z77-recognizing-sticks-ram.html),

However no solution found there. To summarize, all individual slots work (although I haven't stress tested the ram/individual slots) and all the ram is detected it will only ever use 2x4gb totalling to 8gb.

Hardware:
Intel i5 3570k

Asrock Extreme4 z77

4x4gb G.Skill F3-12800cl9d-8gbxl

Antec 520W "gamer" semi modular psu

Inno3d GTX670