PSU raiting for 7800GTX 512mb and how to read it?

[Reckie]

I dont know much at all about PSU's so I got a bit puzzled when out shopping for a new one.

Ive read that to run the 7800GTX 512MB Nvidia suggest using a PSU supplying 20A or was it 22A on the 12V+ line.

I had a look at some Seasonic PSU's yesterday, who one some tests due their good efficency. However, when checking the box for specs it said +12v1 18A and +12v2 18A.

Does this mean it got two lines with 18A each and that the total rating is 18A or does the two lines work together adding up 18A+18A=36A?

 

[CalvinHobbes]

The AMPs and total watts are important. There are two 18A lines on that PSU.

 

[biostud]

Originally posted by: Reckie

Does this mean it got two lines with 18A each and that the total rating is 18A or does the two lines work together adding up 18A+18A=36A?

yes and no. It means that you can draw 36A on the 12V line, but you can't draw more than 18A on each of the rails.

not that it in itself says much but nvidia has a list of SLI certified PSU's: http://www.slizone.com/object/slizone2_build.html

and if nothing else it says that nvidia has approved these PSU's good enough to run two 7800GTX 512

 

[Reckie]

The PCI-Express card only get power from one line then.

Thanks for clearing that up. 😀