You are going to have to check every review possible. I highly recommend the 650D over 600T. I Bought one today
The D14's are massive but the best AIRcooler ever. Make sure you get 1155 one not the 2011.
You could get one 7970 when it's out in jan or a 7950 or stick with 6870's.
SSD is fine and I forgot to put in a HDD, try recycle one if you have one.
You could easily shave more off this by researching differences between motherboards. Dual fan Gcards > Single fan (Cooler and less noise).
Corsair make amazing PSU's Silver and gold rated are good. No experiance with bronze. Though don't buy a *** PSU.
8GB Ram is good but 16 is future proofing.
Windows is windows, check my message to you.
Tl;dr: LOOK and compare everything on reviews.
EDIT: Low profileish ram for the d14's. I warn you of the size.