multiple 12 volt are single? What is better

[Sathsayin]

ok this is the thing. i'm reading online an dsee that my older 15 amp single rail psu of 400 watts is to old. So I'm told that the psu with 12 volt rail with higher amperage is what is needed for modern rigs. compared to older rigs that are more even wattage across the output. Ok here is the deal what is better a single 12 volt rail at 60 amps
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703009
are a multiple rail 4 at 19
http://www.newegg.com/Product/Product.aspx?Item=N82E16817171024
I'm not neccesarly decideing between the two but. I won't to know the disadvantages before makeing a decision. I know the corsair has excellent reveiws. not sure of the other?


so which is better multiple are single and what are the benifits?

 

[Arcygenical]

I personally prefer a single rail design over a multiple rail design... But the difference between the two are small, if anything, these days.

Multiple rails are supposedly better because they "split the load" between the different rails. This allows you to use 1 rail for your GPU's, 1 for your P4 mobo connection and 1 for your hard drives/fans etc. Splitting the load would, theoretically, reduce voltage spikes and dips due to different loads across different components.

The ATX specification, however, already provides good protection against voltage spikes/dips, so the majority of this "feature" is rendered useless. If you exceed the output of a rail (not likely) the rail will trip it's OCP (Over Current Protection) and shut off the PSU. A single rail will never do this, unless you exceed it's power delivery capacity (you won't).

Fun fact - Most PSU's are actually *single rail* designs, but this single rail is then divided into multiple rails, each with their own current monitoring system.

 

[Sathsayin]

alright thanks for the info. I think im going with single

 

[Dangman]

ok this is the thing. i'm reading online an dsee that my older 15 amp single rail psu of 400 watts is to old. So I'm told that the psu with 12 volt rail with higher amperage is what is needed for modern rigs. compared to older rigs that are more even wattage across the output. Ok here is the deal what is better a single 12 volt rail at 60 amps
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703009
are a multiple rail 4 at 19
http://www.newegg.com/Product/Product.aspx?Item=N82E16817171024
I'm not neccesarly decideing between the two but. I won't to know the disadvantages before makeing a decision. I know the corsair has excellent reveiws. not sure of the other?


so which is better multiple are single and what are the benifits?

You really should read this FAQ:
http://www.jonnyguru.com/forums/showthread.php?t=3990

 

[Zero82z]

so which is better multiple are single and what are the benifits?

Short answer: doesn't really matter.

Long answer: still doesn't really matter.

The benefit of a single-rail PSU is that you don't have to worry about accidentally overloading one of the rails, but in practice it's highly unlikely for a rail to be overloaded anyway, so the distinction isn't particularly important. Just make your purchasing decision based on the overall quality of the PSU rather than its design.

 

[Blue Fox]

I only had problems with multi-rail power supplies with a ton of drives.

 

[JonGerow]

I only had problems with multi-rail power supplies with a ton of drives.

That's about it. 8 drive Molexes are going to all be on one rail so that's a lot of load on start up to spin up all of those drives. 4 drives (not including opticals) or less are never a problem.

Also, TEC's are tough on split +12V rails. A TEC could easily draw 5A+ and usually uses Molex power so it's on the same rail as hard drives.

Otherwise, it doesn't make a damn bit of difference if the +12V is split or not. If anything, split is "safer" because if a short overloads a rail, the PSU is going to shut down instead of having the wire overheat and melt insulation.

 

[BillR]

That's about it. 8 drive Molexes are going to all be on one rail so that's a lot of load on start up to spin up all of those drives. 4 drives (not including opticals) or less are never a problem.

Also, TEC's are tough on split +12V rails. A TEC could easily draw 5A+ and usually uses Molex power so it's on the same rail as hard drives.

Otherwise, it doesn't make a damn bit of difference if the +12V is split or not. If anything, split is "safer" because if a short overloads a rail, the PSU is going to shut down instead of having the wire overheat and melt insulation.

I have run into this; the computer starts, runs for a second or two, fans spin up then instant shutdown.

On a dual rail system I have been able to solve probably 90% of these issues with a rebalance of how the power is distributed between the rails. Sometimes the diagnostic is as simple as unplugging a fan or two, especially those half amp 120mm units, and moving them to the other rail.

I have seen a similar issue with single rail PSUs as well but in most of those cases to keep wiring neat people tend to run as much as possible from one, maybe two pigtails and tuck the rest away. In those cases I tend to find warm if not very warm 12v wires running to the components. You can only stuff so many AMPs down an 18ga wire, 14 if you are lucky

 

[JonGerow]

On a dual rail system I have been able to solve probably 90% of these issues with a rebalance of how the power is distributed between the rails. Sometimes the diagnostic is as simple as unplugging a fan or two, especially those half amp 120mm units, and moving them to the other rail.

Are you crimping your own Molexes onto the wire that normally power the P4 CPU connector?

 

[BillR]

Are you crimping your own Molexes onto the wire that normally power the P4 CPU connector?

No, but I'm not talking about my machines, these are ones I see for service.

 

[JonGerow]

Oh. ok.