System Question

[Ethanc]

First of all I would like to thank everyone for all the help. I have recently looked into getting back into W.o.W. I was looking at building a new system that would easily handle 5 WoW instances running at one time. Now I realize the system that I am about to post is over-qualified in some aspects, but why not live by the motto "Go big or go home"?

Case:
COOLER MASTER HAF X RC-942-KKN1 Black Steel/ Plastic ATX Full Tower Computer Case
Motherboard:
ASUS P8Z68-V PRO LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
Video Card:
3GB GTX 580 (only one I found on newegg)
Power Supply:
OCZ ZX Series OCZ-ZX850W 850W ATX12V v2.2 / EPS12V SLI Ready CrossFire Ready 80 PLUS GOLD Certified Modular Active PFC Power Supply Compatible with Core i5 & i7
CPU:
i7-2600k
RAM:
G.SKILL Ripjaws X Series 16GB (4 x 4GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Desktop Memory Model F3-10666CL7Q-16GBXH (Updated to this because it's faster and it's on sale)
Hard Drive:
Intel 510 120GB SSD
WD Black 1TB
DVD Drive:
Basic DvDRW drive
Monitor:
2x 23in Full HD
Operating System:
Windows 7 Ultimate Full


Now the main questions is if the system would be effective enough to run the 5 instances at the same time while recording video. The system would also be used to edit HD video.

All the help would be appreciated, I know that some people are busy buy I don't want to go and build this and a week later a better product come out..

E.C.

(Updated power supply, graphics card, hard drives)


Update: I was looking at an aftermarket CPU cooler and I found one by Zalman. Looked promising to where I would be able to use all my RAM slots. Thoughts if anyone has used one of these before?