A question about RAM speeds

Hi all,

This is my first time posting here so hello! Right, the question ive got is ive recently bought some new RAM and from what i can tell from cpu-z and my bios is that its only running at 1066MHz. The ram itself is OCZ DDR3 PC3-15000 Reaper TC memory which is rated at 1866MHZ. I was just wondering whether its normal for the ram clock to be so much lower and whether its safe to/possible to change the speed of it.

I have a feeling from past experience that someone will want to know what my system is so...:

Asus Rampage II Extreme X58 (bios v.1504)
i7 920 @ 4.0Ghz (Air)
6Gb OCZ PC3-15000 DDR3 TC
ATI 4890 HD

OS Win 7 x64

Also With my overclock, i very rarely get a BSOD but its quite frustrating when it does happen. Ive been reading there are some special rules for the ratios between certain clock speeds. are there any i should be particularly aware of that could cause this?


Thanks in advance for any help

Simon