12v amp rating question.

[nan0_man]

this PSU: http://www.newegg.com/Product/Product.aspx?Item=N82E16817341005
has 4 12v rails. Its sli certified but sli needs at least 12v@34A right? So, the above mentioned PSU wouldn't cut it, or would it?

do you combine the 12v rails to calculate Amperes when theres more than one?

[thideras]

Well, depends what cards you are talking about. If you want to SLi 6800gs's, I'm sure it will handle it. SLi 9800GX2's? Doubt it.

[WonderingSoul]

this PSU: http://www.newegg.com/Product/Product.aspx?Item=N82E16817341005
has 4 12v rails. Its sli certified but sli needs at least 12v@34A right? So, the above mentioned PSU wouldn't cut it, or would it?

do you combine the 12v rails to calculate Amperes when theres more than one?

To calculate the combined 12V amperage among the rails is to find the total wattage produced by the unit and divide it by 12. Amps = Wattage/Voltage. However you can tell by looking at the label in the one side shot of the unit:
"+12V1 & +12V2 & +12V3 & +12V combined current < 50A Maximum"
So the total 12V is greater or equal to 50A. You should be fine for SLI :beer:

[chop_wood]

you can't exactly combine the rails.
If you wanted to quickly guestimate maybe say by adding half the amps per additional rail. The correct way is finding the combined wattage for the rails(usually shows below the amp rating) then divide by 12.... so say you have a 500w psu... with dual 12v rails at 18amps and 350w combined on those rails, it would be 350w/12v which is 29amps ( not 18a+18a which is 36amps)

[chop_wood]

guess wandering soul beat me too it lol

[nan0_man]

Ahhhhh, now I see. Thanks guys.

[nan0_man]

Well, depends what cards you are talking about. If you want to SLi 6800gs's, I'm sure it will handle it. SLi 9800GX2's? Doubt it.

2x7900 GT OC's...
2x SATA drives
1x C.C. Light
2x Pumps(little ones)
5 Fans
?

[WonderingSoul]

2x7900 GT OC's...
2x SATA drives
1x C.C. Light
2x Pumps(little ones)
5 Fans
?

Shouldn't be an issue.

[nan0_man]

niiiice. :)