Elantos

Hey all, I'm planning on upgrading my motherboard, processor and memory soon (since it's now crashing very often, the memory might be a little buggy) but I'm having difficulty in choosing what I want. I'm thinking of either getting i7 920 or 860 with their respective motherboards and memory but I'm not sure what to go for.

So, to start with, what's the difference bewteen the two? The only thing I've picked up on is that the 9xx series are the high end series but the 860 is clocked higher than the 920. The bus speeds are higher though for the 920 but I don't really know what difference that makes.

Secondly with regards to memory, is a 1333mhz triple channel (for the 1366 socket) better than say a 2000mhz dual channel (for the 1156)? The motherboard I might get with the 1366 socket is this one :

http://www.ebuyer.com/product/165434

I have a limited option since my case is matx. It only supports up to 1333 mhz o.c (and I assume o.c means overclocked). The only other matx is the asus :

http://www.ebuyer.com/product/162039

It supports higher frequency ram but it's a little pricy I think.
For the 860, I think I might go for this :

http://www.ebuyer.com/product/173533

With either a 1600mhz or even 2000mhz ram. Does that sound ok? I ask that because when Iwas looking at the specs for the processors, there's a section called memory and listed under it is ddr3 1066/1333:

http://ark.intel.com/Product.aspx?id=41316

Is this the cap on the frequency of ram I need?

Any help and opinions would be much appreciated to steer me in the right direction. Thanks.