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GTX 480 and Epsilon 80plus 700W

Last response: in Graphics & Displays
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April 21, 2010 11:50:51 PM

Hi,

My FSP Epsilon 80+ 700w has 4 12v rails, each offering a maximum of 18A.

The GeForce 480 is spec'ced to require 42a on the 12v rails. Now, do I have 36A on the rails, or 72A?

In other words, do I need to change my PSU?

Thanks.
a b Î Nvidia
April 22, 2010 12:31:09 AM

you have 57a on your 12v rails, you will be fine.
April 24, 2010 12:23:19 PM

Hi, how did you come to the 57a conclusion?
Related resources
a b Î Nvidia
April 24, 2010 12:26:01 PM

You do NOT have enough. You need at least one rail rated at 27A or more.
April 24, 2010 12:41:50 PM

27A? Where does it say so?
a b Î Nvidia
April 24, 2010 12:43:56 PM

eh? Got a link shadow?

Say for example your PSU is 700W Total and has 624W dedicated for the 12V rails

So you then divide 624W by 12 to give you the total amperage your 12V rails can supply

So 624W divided by 12 = 52a (Just an example)

Like ct1615 said you'll be fine.
a b Î Nvidia
April 24, 2010 2:04:23 PM

to the OP, what omgitzfatal stated in his example but you have around 680w total on the 12v

to shadow, you are wrong
a b Î Nvidia
April 24, 2010 2:13:38 PM

He said he has 18A on each 12v rail. He has 4 rails. Does that not mean that each rail can not supply over 18A on its own? You can not simply combine the rails together and say "I have XXXX total."

480 uses 8+6pin, right? He'd need one rail with the 8pin, and one rail with the 6pin. He'd also need to make sure the rail using the 8pin is not feeding the motherboard.
a b Î Nvidia
April 24, 2010 2:20:01 PM

ct,
680 watts looks to be the combined total of all the positive rails, looks like a minimum of 45 amps combined on the 12v, which will increase to who knows what depending on the 3.3 and 5v loads.
Most places do say between 55 and 57 amps total.
a b Î Nvidia
April 24, 2010 3:20:55 PM

ah, i had a small pic to go by, it looked like it said 680 total on the 12v
April 24, 2010 3:23:29 PM

So, no consensus? :) 

April 24, 2010 3:26:07 PM

CT1615 and delluser:

675W is the combination of all the positive rails, but the positive rails that are not 12V rails (+3.3V and +5.0V) are rated 155W. So in theory that would leave a minimum of 520W to the 12V rails, which would leave 43A to the 12V rails.
April 24, 2010 9:53:16 PM

Do you guys think I should buy a better PSU just in case ?
a b Î Nvidia
April 24, 2010 10:12:07 PM

How old is the Epsilon. I think your borderline. If your planning on running a o/c i5 750, I would use that or any reason to maybe get a high quality , single rail 750+ psu. In the end its to power maybe the most power hungry single gpu ever :) 
April 24, 2010 10:31:04 PM

well its not a brand new PSU.

if there were enough GTX 480s on sale there would surely be people trying to run it on my PSU but so few cards, so few samples :( 
!