Ok so I am working on my first build and I don't want to screw anything up. So far I have a P35-DS3L mobo, and am getting an MSI 8800GT 512MB GPU. My case is huge (coolermaster 830) and I will probably add some fans, plus 2 HD, 22 inch monitor, and an e8400. So my question is, do I really need a 600W+ power supply? I was guessing you only need 600+ if you are running 2 GPU's. The main difference I see in the 520W Corsair Modular vs 550 Corsair non modular is that the modular has 3 12v rails, each at 18 amps. The 550W has 1 12v rail, at 41 amps. Will the one 1 12v rail be best for running my single gpu rig? will it be more stable then the modular one?

so, it'll either be this one (modular)

http://www.newegg.com/Product/Prod [...] 6817139001

or this one (non mod)

http://www.newegg.com/Product/Prod [...] 6817139004

unless you think I need the 620 modular.

thanks for the info.

Either way, you could do better on price
VX550 http://www.buy.com/prod/corsair-vx [...] 52646.html
HX520 http://www.buy.com/prod/corsair-52 [...] 70716.html

Ok so I am working on my first build and I don't want to screw anything up. So far I have a P35-DS3L mobo, and am getting an MSI 8800GT 512MB GPU. My case is huge (coolermaster 830) and I will probably add some fans, plus 2 HD, 22 inch monitor, and an e8400. So my question is, do I really need a 600W+ power supply? I was guessing you only need 600+ if you are running 2 GPU's. The main difference I see in the 520W Corsair Modular vs 550 Corsair non modular is that the modular has 3 12v rails, each at 18 amps. The 550W has 1 12v rail, at 41 amps. Will the one 1 12v rail be best for running my single gpu rig? will it be more stable then the modular one?

I am running a e2160 @ 3GHz with an EVGA 8800GT SC on a GA-P35-DS3L on an Antec 380 (yes, that's 380 watts), and if you do the math, it's still overkill.

Power consumption isn't as large as you think it is.
http://www.atomicmpc.com.au/forums [...] t=9354&p=0

Agreed. Those PSUs are rock solid and high quality. 2nd only to the FSP Silencer and a few others.

wow that link from atomic forums was really informative. I appreciate the responses and will be going for one of those two you linked. The only real question I still have is the Amperage on the rails. 1 has 41 amps on one 12V rail, other has 18 amps on 3 12v rails. aren't 12V rails only used for mobos or somthing? why would you need more than one 12V rail?

double post. my bad

Either way (one rail or 3) will work fine. +12V is used for almost everything nowadays. It's the main source for the CPU, for the GPU, a major source for hard drives and MB components, etc.

600 watts is a little over kill, i run my q6660, a antec 900 case, 8800 GTS(G92) vc, 160 gig hard drive, another 80 gig hard drive, 4 gigs or ram on a antec earthpowe 500 watt power supply and all is good with my comp.

The HX-520 is plenty for the system you listed.

A PC Power & Cooling 610 is $119 dirrect from them and is -constant rated- @ 49Amps on 12V with 40C air blowing into it (the Turbo line is rated 50C).
All the 12V power is on one extra regulated rail so it is 100% usable.

600+ is overkill for such a system. 500W will be plenty with reserves, heck, on spcr they have a thred where lots of people report success with 350W on similar systems.

In my book, the less +12V rails, the better, 1 is best.

I don't get why they put 3 12V rails on the Corsair 520WHX Modular. The 550W Corsair has 1 12V rail which higher rated Amps. Why would they put 3 rails on a 520 W PSU? I dont want to underpower my gear with lower amp rated rails, but I also don't know @#$% about cable management. I think I can manage finding somewhere for them to go though since I have a coolermaster stacker 830 and its huge.

Read the review on the HX520
http://www.jonnyguru.com/modules.p [...] ry&reid=18