Dual channel memory is critically important in certain video playback applications such as madVR and SVP.
Single channel: 64-bit data path
Dual channel: 128-bit data path
(If you are familiar with gaming cards, you know what that means.) Personally I recommend DDR3-2133 2 x 4GB such as G.SKILL F3-2133C11D-8GAO
, ~$59, not terribly expensive (DDR3-1600 2 x 4GB costs ~$50 anyway), improving the performance of the above applications considerably, and future-proofing (2133 MT/s is the lowest transfer rate of the DDR4 specs, btw). You shouldn't worry about compatibility, it's compatible with ASRock Z77 Pro4-M (and perhaps almost all Z77 mb).Edited by renethx - 3/7/13 at 4:26am