Building a system for Age of Conan and trying to keep it around 1400USD. Here is what I have so far, would love any input you guys have as I am a few years behind on tech knowledge.
 
   
CoolerMaster Unit 600 Watts eXtreme Power - SLI Supports
(Quad-Core)Intel® Core™ 2 Quad Q6600 @ 2.4GHz 1066FSB 8MB L2 Cache 64-bit
(3-Way SLI Support) Asus P5N32-E nForce 680i SLI Chipset LGA775 FSB1333 DDR2 Mainboard
4GB (2x2GB) PC6400 DDR2/800 Dual Channel Memory (How much does brand matter here?)
NVIDIA GeForce 8800 GTS 512MB 16X PCI Express
320GB SATA-II 3.0Gb/s 16MB Cache 7200RPM HDD
Sony 20X Double Layer Dual Format DVD+-R/+-RW + CD-R/RW Drive
 
Thanks in advance!

Make your CPU a Q9300, some places actually offer it for cheaper than the Q6600 and the Q9300 is based on 45nm technology instead of the 65nm the 6600 runs on.
 
As for RAM brand, you want to make sure the customer reviews are solid and different brands have different heatsinks / heat spreaders for the sticks. If you're into overclocking this can change your decision. If you're not into OCing just head for any solid looking sets of sticks.
 
Everything else looks great from my perspective. You might want to consider a RAID0 set up with your hard drives to help decrease the load times in Age of Conan  (I'm looking forward to it too).

Would my current choice of MOBO still be adequate for the Q9300?