http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-780/specifications
780 Thermal and Power Specs:
95 C = Maximum GPU Tempurature (in C)
250 W = Graphics Card Power (W)
600 W = Minimum System Power Requirement (W)
One 8-pin and one 6-pin = Supplementary Power Connector
SLI - 600 + n x (250) = 850 watts for 2 cards
http://www.guru3d.com/articles_pages/geforce_gtx_780_review,9.html
Subjective obtained GPU power consumption (780) = ~ 231 Watts
Here is Guru3D's power supply recommendation:
GeForce GTX 780 - On your average...
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-780/specifications
780 Thermal and Power Specs:
95 C = Maximum GPU Tempurature (in C)
250 W = Graphics Card Power (W)
600 W = Minimum System Power Requirement (W)
One 8-pin and one 6-pin = Supplementary Power Connector
SLI - 600 + n x (250) = 850 watts for 2 cards
http://www.guru3d.com/articles_pages/geforce_gtx_780_review,9.html
Subjective obtained GPU power consumption (780) = ~ 231 Watts
Here is Guru3D's power supply recommendation:
GeForce GTX 780 - On your average system the card requires you to have a 550 Watt power supply unit.
GeForce GTX 780 2-way SLI - On your average system the cards require you to have a 800 Watt power supply unit as minimum.
GeForce GTX 780 3-way SLI - On your average system the cards require you to have a 1200 Watt power supply unit as minimum.
If you are going to overclock your GPU or processor, then we do recommend you purchase something with some more stamina.