Guys i have problem with my m4e.

First i have 4gb of corsair dominator 1866mhz installed on my mobo. Later i put 4 gigs more ( so 4x2GB ). And now i have BSOD, memtest fail. When i checked each mem - all is ok, i checked memory slot - all is ok. And the strange thing, is that when i set mems on 1600mhz 1T 9-9-9-24 all is ok, in stock clocks - 1866mhz 2T 9-9-9-24 - bsod What can be wrong ?