Question about 12v for 2 PSU.

[ajy0903]

I had a question about 12v part of 2 PSU.

I was looking at these two PSU:

Antec EarthWatts EA-650

+3.3V@24A, +5V@24A, +12V1@38A, +12V2@38A, [email protected], [email protected]

Antec HCG M Series HCG-620M

+5V@24A, +3.3V@24A, +12V@48A, [email protected], [email protected]

And one graphic card that I looked at, "EVGA 03G-P4-2782-KR GeForce GTX 780 3GB", requires:

600 watt or greater power supply with a minimum of 42 amps on the +12 volt rail.

The question that I have is, can Antec EarthWatts EA-650 has amp requirement for above grapic card?

 

[OptyTrooper]

Go single rail e.g. your second choice.

 

[ajy0903]

Go single rail e.g. your second choice.

Oh, ok.
Thanks for reply.
So, your saying several rail doesn't combine into one big amp, right?

 

[OptyTrooper]

Oh, ok.
Thanks for reply.
So, your saying several rail doesn't combine into one big amp, right?

Correct.

 

[ajy0903]

Correct.

Then what are the usage of multiple rail of 12volts?

 

[Bobnova]

Nothing is going to draw more than 38a on a given rail, either one of those will be just fine.
The only time multiple rails will cause an issue is if they're very small rails, 12a or somesuch.
On big units single rail is significantly more dangerous in the event of a short circuit.

Correctly sized multiple rail is safer and just as functional as a single rail.

 

[OptyTrooper]

If Bob says it's so it's so. Once upon a time it was conventional wisdom that single rail PSU's were better but I am likely stuck in the past.

 

[Bobnova]

It was conventional and correct wisdom at one point, the first Intel spec for multi-rail put all the PCIe connectors on the second rail. That was a major issue for SLI/CFX/high end GPUs. That said, it was also an ~18 amp rail as opposed to 38, that didn't help matters.

These days PSU manufacturers (and Intel, I think) have realized their error and done a rather better job of it.

 

[NiHaoMike]

Multiple rails also help isolate (electrical) noise but that's rarely a problem in a PC.

 

[ajy0903]

Oh, ok.
Thanks for reply.
So, because of "EVGA 03G-P4-2782-KR GeForce GTX 780 3GB", requires:

600 watt or greater power supply with a minimum of 42 amps on the +12 volt rail.

If I choose between above PSU models, I should choose, "Antec HCG M Series HCG-620M", right?

 

[Bobnova]

It wants that for the full system, the card actually draws ~20 amps at 100% full load.

Like I said, either PSU will work fine.

 

[ajy0903]

It wants that for the full system, the card actually draws ~20 amps at 100% full load.

Like I said, either PSU will work fine.

Oh, ok.

Cause I was thinking of buying the "full system" in future.

New motherboard, new processor, new ram (min 2 for dual channel for 2-4 sticks), new graphic card, new/old HDD (min 2) and etc.

 

[ajy0903]

PSU that 600 watt or greater power supply with a minimum of 42 amps on the +12v?

Are there "PSU that 600 watt or greater power supply with a minimum of 42 amps on the +12v?"

I asked on here for the only upgrade situation.

But, "PSU that 600 watt or greater power supply with a minimum of 42 amps on the +12v", -> is for entire system, according to replier on that above link.

So, I was also thinking of building entire new system with buying "every components that I need", including new graphic card (maybe GTX 780) that was requiring, "PSU that 600 watt or greater power supply with a minimum of 42 amps on the +12v".

 

[pigpottomus]

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139021

This??

 

[ajy0903]

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139021

This??

Cool, thanks for reply.