OCing RAM is questionable at best. In your case, the difference between 1333 and 1600 in terms of performance is minimal. When you start OCing memory, and using your memory at 1600 is indeed OCing it, all sorts of odds things can happen.
If you are going to OC RAM, do so in baby steps. Make very small changes at a time and make sure your overall system is 100% stable after each change. Also, don't try to push your RAM faster than the rating of what you have (1600 in your case).
If I were you, I would run my RAM at 1333 and look at increasing my system performance by OCing the CPU and GPU.