Beautiful setup. What are you using to hook up two PSUs?
Isn't 1200W x2 a but overkill? I assume you got this setup for the 6+2 pins you needed. I mean you need 12 x 6+2 plus 6 molex. That a lot.
Also only two risers are powered? What about the rest?
The best board i found so far: Gigabyte 990FXA-UD3, cheap, no presence jumper needed and very easy to setup. I am running 4 of this boards with 6x290, 4x290, 4x290, 5x280x. To run 6x290s you need windows 8.1 with all updates, has its own driver for 290/290x. Dont use AMDs driver.
My setup for 6x290s:
Board: GA-990FXA-UD3
Processor: AMD FX-4300
Ram: Kingston DDR3-1600 (2x4Gb)
HD: SSD Kingston 120Gb V300
Power: 2 x Thermaltake Smart w1200
Wifi: Tp-link mini 300Mbps USB
GPUs: 2 x Sapphire R9 290x + 4 XFX R9 290
Riser: 2 x1-1 powered + 4 x16-16
O.S.: Windows 8.1 Enterprise
CGminer 3.7.2
CGwatcher
CGremote