THE UNKNOWN said:
As i can see you choose h61 board means SB BRIDGE [ suppose your using i5 2500k ] it support 1066/1333mhz if you get 1600mhz then clock speed of memory will downgrade its speed that mean 1333mhz and in 1600mhz and 1333mhz there isnt noticeble difference
ram can be set in Bios (or uefi) to the correct 1600mhz on many boards. check the manual. intel chipsets revert to lower speeds by default. a common issue.
not huge, but increasing ram to stated speed should nudge the WEI a point or two.