if you are planing to stay with that 1.659v on memory, then take care of cooling them! even with only 0.1590v rise of memory volt maybe too much for them in normal system.
i would get them back with 1,5v and try again, with lover settings if must. what your memory maker think is "safe volts" to your sticks?
Edit: So you have "watercooling"(H50) on your CPU? ...i would recormend putting another casefan to blow air in to those nb and power , heatsink left side of CPU socket.
...Normaly active fan on CPU cooler blow some air to them now they get very little flow and you raise your voltages. might be reason for some unstablenes.
CPU: AMD FX-8150 MB: ASUS Crosshair V Formula DDR3: 2x4GB G.Skill Sniper DDR3-1866
GPU: ASUS 7970 SSD: 4x Corsair F3 120GB @ Raid0 PSU: SF Golden Silent 500W OS: W7 Ultimate 64bit