RAM confusion - Box says 1866Mhz, CPU-z says 1600

Wort

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Dec 14, 2013
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hey guys. I'm confused. Few months ago I ordered G. SKill Sniper DDR3-1866. It was supposed to be 1866 Mhz and the box says it's 1866 aswell, but when I run Speccy or CPU-z it says 1600Mhz. ???

Edited: Even stickers on RAM sticks say DDR3-1866