Random Freezing/Crashing Issues with a new build

I built a new computer a couple months back and ever since I've been getting ridiculous amounts of freezing/crashing issues and I have no idea what the problem is. I've run every test imaginable and RMAed my RAM once but to no success. Please any tips/advice would be fanastic! Here is my build:

PSU XFX Black Edition 750W

Mobo Asus P6X58D-E

CPU i7-930

RAM G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3

GPU EVGA GeForce GTX 460

HDD WD Caviar Blue 640gb

DVD Drive

The only thing left I can think of is that I need triple channel RAM, but I've already tried a set of triple channel to no success, and this dual channel is on the QVL list.