Identifying rails on non modular PSU

[specks]

How do you identify the different 12v rails on a non modular PSU?

 

[Eric_On_Web]

I am not sure but I think that you can look at the number of heatsink in the psu itself. Metal cooler rising up. It cools from there and the rectifiers I think are sticked on it to cool down. But I'm not an expert.

 

[Mussels]

How do you identify the different 12v rails on a non modular PSU?

with great difficulty, usually. i'm interested as to what people come up with here.

 

[slyfox2151]

with great difficulty, usually. i'm interested as to what people come up with here.

depending on the amount.... if there are 3 rails, i assume one is on the ATX 12v cpu 4/8pin cable... then 2 or 3 of the outputs are another rail then the next 2 or 3 next to each other are the other one.



no hard facts or anything to back this up... just common sense or logic would dictate this....



EDIT:
just realised you said ! NON MODULAR ! sorry about that.



in witch case you would need to open the PSU and follow the wires.

 

[Frick]

I wouldn't trust the cheapest PSU's to use logic anyway.

I assume the best way to make sure is to look at the board itself.

 

[theonedub]

Pop it open or find a review that did it for you.

 

[claylomax]

You usually get the information on the psu itself, on one of the sides.

 

[Wile E]

A lot of them will have a different colored stripe on one of the yellow wires for each different rail.

Like rail one will have a solid yellow wire, while rail 2 while have yellow with a blue stripe, while rail 3 might be yellow with a black stripe, etc., etc.

 

[Eric_On_Web]

A lot of them will have a different colored stripe on one of the yellow wires for each different rail.

Like rail one will have a solid yellow wire, while rail 2 while have yellow with a blue stripe, while rail 3 might be yellow with a black stripe, etc., etc.

True on that. Had one of 2 rails and all 12v lines were yellow wires but the 4 pins plug for the cpu were yellow-blue stripped. With 15amps each means the cpu could be up to 150w but in fact with a normal 70% efficiency psu should be less of course.

 

[specks]

i've read that for common dual 12v rail PSUs have one rail for the atx12v and the other rail for other stuff..is this true?or may it vary from PSU to PSU?

 

[slyfox2151]

True on that. Had one of 2 rails and all 12v lines were yellow wires but the 4 pins plug for the cpu were yellow-blue stripped. With 15amps each means the cpu could be up to 150w but in fact with a normal 70% efficiency psu should be less of course.

efficiency only affects input power, not output. a 500 watt PSU @ 80% efficiency under full load will pull more then 600 watts AC from the wall.

 

[Swamp Monster]

I agree it's hard to tell and you're lucky if different rails has markings, like colored stripes.

If it's cheap/old PSU, then "Dual rail 12v" means that has really a single 12V source (one common transformer for all 12V) and only thing that means "dual Rail" is OCP on each rail in best case. Mostly OCP on cheap PSU's don't work as intended anyway.
In worst case all 12v wires are soldered together inside and there is actually no dual rail at all.

Summary is: you need to put even load on all wires and watch how hot they get on load. If they are evenly warm, you're doing it right.

 

[overclocking101]

this is why i buy single rail psu's. you dont have to worry about any of this, but USUALLY it goes: dual rail: 12v/4/8pin/1 pci-e on rail one- rest on rail 2
quad rail: 12v rail one=4pin/8pin/1 pci-e rail 2, rest of pci-e rail 3, everything else rail 4

 

[specks]

Sorry to be off topic. Can you guys recommend me a good single 12V rail, 500W or above, and around 35amps or higher PSU for $50 or less. Thanks.

 

[specks]

dual rail: 12v/4/8pin/1 pci-e on rail one

Can you please clarify what are these

Sorry im a noobie

 

[PaulieG]

Sorry to be off topic. Can you guys recommend me a good single 12V rail, 500W or above, and around 35amps or higher PSU for $50 or less. Thanks.

That's really hard at $50 or less. You are asking alot there. A few bucks more will get you something respectable. The PSU is the foundation of your system. It's the last component you want to go cheap on. Here are the only recommendations that I feel good about for "around" your budget. Anything less, and you are asking for trouble, IMO.

CORSAIR Builder Series CX500 (CMPSU-500CX) 500W AT...

XFX Core Edition PRO550W (P1-550S-XXB9) 550W ATX12...

 

[streetfighter 2]

Not that I don't agree with the wise Paulieg, but I don't entirely concur either :
Rosewill Green Series RG530-S12 530W Continuous @4...
$55 + $2 s/h (USA)

If you keep your eye on it it drops to $50 with free shipping occasionally. The PSU is actually made by ABS (respectable IMO).

 

[newtekie1]

How do you identify the different 12v rails on a non modular PSU?

It doesn't usually matter, most multi-rail PSUs are single rail anyway.

 

[Mussels]

It doesn't usually matter, most multi-rail PSUs are single rail anyway.

that is true now, i've seen this stated elsewhere.


due to complicated legal/ATX spec reasons, they state they're multi rail when they arent. when an expert pops them open they realise its just a single rail PSU advertised as multiple.

 

[newtekie1]

that is true now, i've seen this stated elsewhere.


due to complicated legal/ATX spec reasons, they state they're multi rail when they arent. when an expert pops them open they realise its just a single rail PSU advertised as multiple.

Yep, the only thing that makes it a multiple rail PSU is that they have multiple Over Current Protection curcuits to protect the wires from melting if some idiot user desides to plug everything in their computer into a single 4-pin molex run.

If you spread the load out properly, a "multiple rail" psu will never be any different than a single rail PSU. And worst case, if you don't spread the load out properly, you trip the OCP and the PSU shuts down before you do any damage, unlike a single rail PSU which will just let the wires melt and burn.

 

[Mussels]

Yep, the only thing that makes it a multiple rail PSU is that they have multiple Over Current Protection curcuits to protect the wires from melting if some idiot user desides to plug everything in their computer into a single 4-pin molex run.

If you spread the load out properly, a "multiple rail" psu will never be any different than a single rail PSU. And worst case, if you don't spread the load out properly, you trip the OCP and the PSU shuts down before you do any damage, unlike a single rail PSU which will just let the wires melt and burn.

well thats how it works with QUALITY PSU's, i've had some average ones that just let the voltages droop and cause stability problems (even on stock machines, things like HDD's powering down due to low voltages, etc)


the moral really is buy a quality unit and dont overload it.

 

[v12dock]

Simple, buy a single rail PSU

 

[newtekie1]

Simple, buy a single rail PSU

You think a cheap single rail PSU is a good idea over a quality multi-rail?:shadedshu

If you buy a quality PSU, single or multi rail won't matter. If you buy a cheap PSU, single or multi rail won't matter either, the PSU is still going to be junk.

 

[v12dock]

You think a cheap single rail PSU is a good idea over a quality multi-rail?:shadedshu

If you buy a quality PSU, single or multi rail won't matter. If you buy a cheap PSU, single or multi rail won't matter either, the PSU is still going to be junk.

I'm thinking TX750, high quality single rail

 

[Frick]

You think a cheap single rail PSU is a good idea over a quality multi-rail?:shadedshu

If you buy a quality PSU, single or multi rail won't matter. If you buy a cheap PSU, single or multi rail won't matter either, the PSU is still going to be junk.

This. I kinda agree with OklahomaWolf in his Corsair AX1200 review with that 100A on a single rail thing though.