G.Skill 1866MHz RAM registering as 1600MHz.


Dec 17, 2009
Hey everyone,

Recently I built a new PC and included two sets of: G.Skill RipJawsZ 16GB (4x4GB) DDR3 PC3-14900C9 1866MHz.

However on AIDA64 each DIMM shows as: G Skill F3-14900CL9-4GBZL 4GB DDR3-1600 and in BIOS the target DRAM speed is 1600MHz as well while the ‘Memory Frequency’ setting is set to AUTO . I tried setting this to 1866MHz but I receive an ‘Overclocking failed’ message and I’m forced to reset it to AUTO.

Also in CPU-Z under the Memory tab DRAM frequency is registered as 800.5MHz, other PC components are:
ASUS Rampage IV Extreme
Core i7-3630K CPU
GTX 570 SLi

Why am I not achieving 1866MHz with is RAM, is there something I need to enable on the motherboard?