atfrico

Single rail is recommend it below 1500watts, multi-rail is to fully use the 1500w and more, for that you need the 230v installed in your house/apartment.

lehpron

rahulsarin
What configuration do you suggest I go with if CPU = i7 3770K and GPU could be:

1. Single GTX 690
2. 2x GTX 690
3. 2x GTX 680 Classified

Thanks in advance for your help!

To be quite honest, you didn't need that PSU for any of those configurations, with any overclock.  You could have gotten a 1000W unit and saved some major cash, but there is a lot of future-proofing using the EVGA PSU, so I respect that decision provided you knew about it.

First see this link, understand what it says, as I've estimated PSU requirements for others before.  For your three intended configurations, the total current draw at stock ends up as 32A, 57A and 40A, respectively from 12v alone and without drives and fans.

Overclocking tends to influence power draw exponentially, where 40% higher frequency leads to doubling the power.  But only the CPU is expected to get that high, graphics cards' tend to average 15-20% higher than stock.  Either way, for all three configurations the current draw from 12v ends up 43A, 73A and 52A, respectively from 12v alone and again without drives and fans.

You bought 1500W with a maximum possible current load in single-rail of 131A; the way I see it, you could take advantage of the ten-year warranty as this PSU could easily be salvaged for the next several builds.   EVGA's NEX PSU is more meant for really pushing hardware like their SR-X board with a pair of 8-cores Xeons and 4-way SLI GTX680's, which can soar above 110A.