Sandy bridge only supports up to 1333Mhz. Check your bios and see if you have an XMP setting, you may be able to force it to work.
http://www.intel.com/consumer/game/extreme-memory.htm
I did this recently and the best way I have found to do it, is to move anything important to another drive, reinstall windows, then clone the windows drive.
I currently have an MSI GTX 960 4GB edition.
I was was hoping to upgrade my current system and pass on my current gpu to my younger brother, who is just now getting into PC gaming.