Thanks for the update.
Your configuration + OS, > http://pcpartpicker.com/p/tnhGnQ
The Corsair 850i will easily support your configured system.
Chart of total system draw for various GPUs, > http://www.guru3d.co...nchmarks,4.html
Similar question for PSU/GPU configuration,
Looking at this site with there new test platform, much beefier than your proposed, testing R9 290 CF.
Note the change from the old PSU to the Corsair AX860i
"The Intel X79 platform that we used to test the all of the video cards was running the ASUS P9X79-E WS motherboard with BIOS 1501 that came out on 01/15/2014. We went with
the Intel Core i7-4960X Ivy Bridge-E processor to power this platform as it is PCIe 3.0 certified, so all graphics cards are tested with PCI Express Gen 3 enabled. The Kingston
HyperX 10th Anniversary 16GB 2400MHz quad channel memory kit was set to XMP Profile #2. This profile defaults to 2133MHz with 1.65v and 11-12-12-30 1T memory timings.
The OCZ Vertex 460 240GB SSD was run with latest firmware available. A Corsair AX860i digital power supply provides clean power to the system and is also silent as the fan
hardly ever spins up. This is critical to our testing as it lowers the ambient noise level of the room and gives us more accurate sound measurements than the old Corsair AX1200
power supply that we used from 2012 till this year that had a loud fan that always ran."
Read more at http://www.legitrevi...0IBvRiZW7u56.99
The total system draw was 743W. = 61.9. if you take the draw from the R9 295X x 2 = 793W = 66 Amps, the AX860i rated at 71 Amps, still gives you wriggle room.
I would choose the AX860i.