Originally posted by: Algere
Originally posted by: diabloII
2. +12V1 [18amps] +12V2 [18amps]; does this mean i get a total of 36A delivered through +12V?
It means each rail can hold up to 18A maximum per spec, not how much amps it has. The amp amount listed under +12V total (32A for 485W model e.g.) is what those PSUs have in total. That total is split & balanced between those two rails based on power draw. For example if the components on one rail draws 17A, the other rail would have 15A left to use or if the draw on one rail is 16A, the other rail would have 16A to use.
Originally posted by: ^Sniper^
I just bought the Enermax EG495AX-VE which is about the same except mine has a couple different features. What is does is use one 12v rail that just supplies power to the mobo,CPU and video. The other rail powers optical drives,HDD drives,fans,ect.
Ya sure about that? My manual says CPU, Mobo, & SATA on one rail, and drives, floppy, & external gfx card power on the other.
Originally posted by: ChicagoPCGuy
The idea is that fluctuations of power on one 12v rail will not affect the other 12v rail, thereby increasing system stability. For the most part, it is a great idea. Where you will find some people object to this is when overclocking--they want as much amps on the 12v rail as possible, and therefore opt for a single 12v rail PSU with a high amps on that rail.
As a counter argument & as you've said dual rail PSUs increase stability - multi rail PSUs increase the stability factor further. That too is important in OC'ing. With single rail PSUs, you get high amps but less stability than a dual rail PSU if those amps are heavily used. At the opposite end a dual rail PSU has better stability at higher loads than a single rail PSU but lower amps usable (in most cases).
Basically if dirty/unstable power was limiting your overclock, you'd want a 2+ rail PSU. On the other hand if the lack of amps/power was the limiting factor, you'd want a single rail PSU. Now if you want the best of both worlds and/or needed more power than the strongest single rail PSU out there (Zippy 700W?), your only sensible option would be a high powered multi-rail PSU.