I've had this issue on 2 x58 mobos so far, where all memory channels not detected, and even blue screens. How careful were you when you installed the cpu, when you opened the latch for the first time, you didn't accidentally brush the socket pins with your thumb? Just to be sure I would check the cpu socket pins and make sure none are bent. I unbent mine, and now all ram is detected, and mobo is stable.
This is only when I try to get speeds over 1900MHz this happens on 1600MHz and 1866MHz I see full 12GB regardless of me increasing or decreasing the QPI/VTT Voltage.
Edited by shadowman007 - 9/25/11 at 4:28am