power supply confusion

dz9c

im looking for a power supply. a lot i see have 2 12v rails. i only need one i guess for a graphics card. the graphics card asks for 22amps on a 12 v rail but there are 2 and they only have like 18 amps each. if one isnt being used, does it donate the power to the other?
example: 2 12v rails at 18amps each. use only one graphics card so you get 36 on that one rail. right?

Helios

Your graphics card asks for a total of 22 amperes, on both rails.
So if there are 18 amperes on each rail, you get 36 amperes.
What the graphics card will use specifically? Well, that's complicated. But know only one thing: when in the system recommendations they tell you that you need 22A on 12-V, then it's a total of 22A on both rails.

What's the maximum price you can pay for a power supply?

dz9c

ohh! thank u that explains it now cuz i was having trouble finding a power supply in my price range with 22amps on one rail cuz most of them have 2 12v rails.
im in the 30-40 range. maybe 50

i was looking at this one by ULTRA on tigerdirect its 600 watts and it actually has 35 amps on one rail so this would def be a good buy, i think.
[url]
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2974503&sku=ULT33136%20K[/url]