there are new bios out from asus for updating the cpu and memory for most of there mb check to see that your bios is up to date. also as that a 3 dimm kit it sounds like it was made for the x58 mb. did you check to see if that ram was on the mb ram guild?? most new ib/sb ram is 1.5v rated. with some using a 1.6-1.65 max voltage of the ib/sb spec.
The Ram is compatible. I checked the manual and online. I have downloaded the new BIOS and the problem still persists. Still only allowing me to use one 2gb stick.