I don't forsee this being an issue, but its been a long time since the multiple 12v rails have been a hit. I recall the more rails (as long as they were decent amps), the better.
Anyhow, I've got an Etasis 750w PSU with 4 x 12v rails at 18a per rail. Planning on using this for the P67 Sabertooth, I5-2500k, 2 x 8gig Corsair Vengeance 1600 system that I just purchased last night.http://www.overclock3d.net/reviews/powe ... dsli_psu/7
I bought this thing about 2 years ago in anticipation of a new computer build. I got it for a screaming deal at the time of 49.99 (not counting shipping to Alaska unfortunately). I realize its based on an older design, but everything appears to be pretty rock solid with this PSU from the looks of reviews on it. I just recently pulled it out of the box for the first time since I purchased it and confirmed it on a spare system, boots it up fine and ran the system for a little over a day.
My plan is to make sure that I plug the auxiliary 6pin PCI-E connectors into GPU from the different 12v rails to spread the power out to different rails, which should make it run pretty stable. If I dedicated 2 of those rails to the video card alone, I should be golden. That leaves the other 2 rails for use with other components like drives and fans, ect. Any flaws in that logic?
The video card I'm considering slapping in this rig is a 6950 which was stated as needing a 12v rail with an amperage of 30 total. Since these are 18a rails, 2 of them would be 36, keeping me safely within that requirement.