PSU - Are my wattage calculations correct?

Som3one

Honorable
Jun 13, 2013
719
0
11,160
Hey there,

I currently have a Corsair AX760i PSU with a i7-4770k @ 4.2GHz and one Gigabyte Windforce GTX 780 @ stock.
I might have the chance to get my hands on another GTX 780 but I was wondering if my PSU would be strong enough.

Judging by Corsair Link, my PSU deliver around 450W-470W when running Prime95 and Furmark at the same time.
As far as I know a GTX 780 draws around 250W-270W. So, I would be able to SLI two of them with my PSU, right?
I know there might not be much headroom for overclocking though.

Also, stupid question: Assuming my system would draw more power than my PSU can deliver, what would happen? I assume the system would just crash, right?
Worst case would be I kill the PSU?
 

JOHNN93

Honorable
lets say you system draws at max260 without the gpu just in case.
the gpu has a tdp of 250 watts.the 12 volt rail on your psu can output 756 wats.for one gpu you are perfectly fine.drawring 510 wats.
if you had a second gpu you whould draw 760 wats.exactly the wattage your power supply can handle.
i personaly dought you whould be able to power it on.