2 12v @ 16a can run gtx 260?

mb203

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Hello, I'm a little confused on how multiple rails provide power. I'm looking into buying a gtx 260 which wants +12 Volt current rating of 36 Amp Amps with a minimum of 500wat psu.


My current PSU is 550w, on the power sticker it has 2 +12v with 16A each. This wouldn't be enough to haul the gtx 260, would it?

Thanks
 

tkgclimb

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What is the specific amount of wattage allocated to the 12v rails, because amps x volts = watts
so 32amps (16x2) x 12v = 384 watts, if it is this amount then your PSU truly pulls 32 amps.
This is easier with single rail PSU's becasue they always can pull the amps they are specced for, the multiple rails are kinda virtual things, that help prevent to much current overload.

But 32amps still isn't spec so to be safe no, i wouldn't do it, but if you have a high end PSU (corsair and such) and not a lot of other loads on it then maybe(manufactures kinda overate these things sometimes), but you really don't have enough power.
 

4745454b

Titan
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I'm guessing here you'll want to buy a new PSU. First, using tkgclimb's numbers, your 550W PSU doesn't output nearly all its power on the 12V rail. Second, your rails are 16A each, which is below what modern PSUs have. (17/18 or 20 is normal.) These things lead me to believe you have an older PSU. Older PSU with newer power hungry GPU will end badly. If I'm right, do yourself the favor of buying something that won't fry your system.
 

tkgclimb

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good logic and I agree, though 16 amps is low you might see it on a low end PSU like a 350 watt but on a 550 watt it probably is pretty old or just not a great PSU. Either way it is dangerous and though you could easily be find, get a new one to be on the safe side, plus a good 550 isn't that expensive. If you have an old PSU than a new one would probably be more efficient and possibly save you money in the long run (just something to think about).
 

tkgclimb

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This is true, but a GPU isn't the only thing that draws Amps of the 12v line, CPU, and drives also do. The amps is an estimate of what you'll need or should have to be on the safe side, just like the wattage requirement.