GTX 780 in SLI

[arm1234]

Here is my current set up. Specs:
Case : Fractal Design Define R4 Black windowed version
Mobo : ASROCK Z87 Extreme 4
CPU : i5-4670k, OC'd at 3.7 (Just to be safe, First overclock)
CPU Cooler: Corsair H90I (Closed Water Loop)
RAM : 2x4GB Corsair Vengeance DDR3
GPU : EVGA GTX 780 3GB Superclocked
HDD : Seagate 1TB 6.0GB/s
SSD : Samsung 128 GB 840 pro series SATA3
PSU : Seasonic M12 II 750 W Modular
Lights: LOGISYS Cold cathode lights
Drive: Asus Blu-ray, DVD drive

I am trying to put a second GTX 780 in my system. I was wondering if I should upgrade my PSU as well, or if my current one will support the power need? If I do need to upgrade the power supply, I had been looking at the Corsair 860 if you can recommend any other unit that would be appreciated!

 

[ubercake]

You won't have to upgrade the PSU.

The standard edition 780 uses 250W max:
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-780/specifications

Here's a review with 780s in SLI listing the power usage as 'System Wattage with GPU in FULL Stress = 617W' on a system with an i7-3960X with an overclock to 4.6GHz:

http://www.guru3d.com/articles_pages/gtx_780_ti_sli_geforce_review,4.html

The 3960 has a much higher power requirement than the 4670 to begin with.

The superclocked editions of the EVGAs use the same as stock (250W max):
http://www.evga.com/Products/Product.aspx?pn=03G-P4-2783-KR

So even if you picked up a second 780 superclocked edtion, you'll have some wattage for an overclock using your current PSU (but who needs to OC their 780s when they have two???).

 

[ahnilated]

Here is the specs for just 1 card:

Thermal and Power Specs:
95 CMaximum GPU Temperature (in C)
250 WGraphics Card Power (W)
600 WMinimum Recommended System Power (W)
One 8-pin and one 6-pinSupplementary Power Connectors

 

[arm1234]

You won't have to upgrade the PSU.

The standard edition 780 uses 250W max:
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-780/specifications

Here's a review with 780s in SLI listing the power usage as 'System Wattage with GPU in FULL Stress = 617W' on a system with an i7-3960X with an overclock to 4.6GHz:

http://www.guru3d.com/articles_pages/gtx_780_ti_sli_geforce_review,4.html

The 3960 has a much higher power requirement than the 4670 to begin with.

The superclocked editions of the EVGAs use the same as stock (250W max):
http://www.evga.com/Products/Product.aspx?pn=03G-P4-2783-KR

So even if you picked up a second 780 superclocked edtion, you'll have some wattage for an overclock using your current PSU (but who needs to OC their 780s when they have two???).

So if I dont plan on overclocking my cards 750W will be able to handle the load of 2 780's? I notice you have 2 780's in your system. Is it as awesome as I am hoping it will be?

 

[ubercake]

Your power supply will definitely handle 2x780s. That Seasonic can provide up to 744W on the 12V rail (62A).

This is more than enough for your system with 2x780s. That PSU also has 4x6+2 pin PCIe power connectors. You're all set.