I don't see much to gain by overclocking your RAM, but if you are really willing for whatever reason, you can do it by changing RAM settings ont the BIOS. Your motherboard is certified up to 1866.
Anyways, I'm sure it will make very little improvement, and you will very likely have issues. I never damaged a RAM stick by overclocking it, by I can assure you running a computer 5% faster is no use if it restarts every five minutes.