Why is my Mobo defaulting my 1866mhz ddr3 to 1333mhz?


Feb 17, 2012
Hey guys , hows it going, new the the forums, I appreciate in advance any help that you can offer me.

I'll start by listing my system specs:

AMD FX 8150 @ 3.6ghz (stock, although the mobo auto tunes it to 3.9ghz, plus TurboCore; I will be overclocking once I understand the damned bios more) -- Corsair H80 cooler installed with some noctua pf-12 fans.


16gb Patriot Division-2 Viper Extreme 1866mhz DDR3

MSI AMD Radeon HD 7970

Corsair FORCE Sata3 SSD 120gb

Corsair TX750 psu

Windows 7 Ultimate 64-bit

So my issue is I can't seem to get my ram to show as higher than 1333 in windows (showing 667 in CPUID). The highest I can get it to show in the bios and still boot is 1600, but even then it seems to revert to 1333 in windows. The Ram is rated at 1866mhz 9-11-9-27, which I've read my motherboard and CPU should support.

So I'm using this PC for home gaming if you hadn't guessed.... do I need to take out 8gb of ram or something? I realise 16 is way overkill for a home gaming comp but I just grabbed it since memory was so cheap got the whole 16gb for $105 after tax.

Any response greatly appreciated.

I say this over and over again. RAM is sold at the fastest rate it is warranted to work at, not at the speed it will run when you plug it onto your board. The speed it runs at by default is set by your motherboard/cpu combination. 1333mhz is the default speed for your processor/motherboard combo. To set it at anything other than that, you have to specify it under the RAM settings in your BIOS. (in other words, you have to overclock it to the settings you want to reach)