Wondering why you chose an H67 motherboard. They don't allow you to overclock and you are already buying a 6850 so you don't need the integrated graphics. I would recommend a P67 instead with an x8/x8 PCIe configuration so you have the potential to upgrade. Also, many motherboards support both SLI and Crossfire but double check to make sure the motherboard you choose supports your graphics card choice.
Also, if you plan on overclocking, you may want to consider 1600MHz RAM. BTW I don't consider 8GB to be overkill.
I was going to suggest dropping it to a 650 or 600 as well but You choose a good model with bronze certification so I left it alone. AMD graphics cards use significantly less power then their Nvidia counterparts. you could probably run an overclocked processor and 2 6850's on a 450W if you wanted to. 2 6850's in crossfire with an overclocked i7-920 only draws 423W at the outlet during Furmark (which produces inflated results anyways) And that is 423 at the wall. Factor in 85% efficiency and the psu is only putting out 359W.
I thing the Green HD gonna make you impatient....and I'd wanna OC a bit to speed things up.
Why would you say that? Green HD would only be used for storage, mostly be using SSD for everything else, OS, Visual Studio, and should have more than enough space to hold my projects to compile from SSD