ASUS M4A78T-E AM3 & G.SKILL 4GB (2 x 2GB) F3-12800CL9D-4GBNQ

[Tradesman]

Prob not the DRAM (easy enough to test each stick), may be mobo, but basically the 055 can't carry 4 sticks at 1600, even with a 965 it can be hard to run 4 sticks. Have you looked at the AMD/1600 set up thread:

http://www.gskill.us/forum/showthread.php?t=7688