PSU - combine 12V1 & 12V2

[loopy83]

My PSU have one 12V lane with 20A (+12V1) and a second lane with 18A (+12V2).

Will the PSU combine both lanes automaticly, when i need more then 20A ??
How can I get 30A from these PSU?

kind regards
Loopy

[adamsleath]

yes; what is the combined rating for 12v output?
just look up yr psu with google :)

depends how good yr psu is as to how it performs at higher loads / amps

"technically" how are the lines separated i wouldnt have a clue.

20+18 A rails should give you 30A combined i would have thought, but it may not; depends what exact psu you have and what it was designed/made to output

what do the manufacturer spec's say?

[loopy83]

the sticker says max 360W in both 12V lanes... is that the answer to my question? Is that the combined power?

12V1 + 12V2 = 30A => 360W...

[tiro_uspsss]

12 x 30 = 360

so if one line has 18A : 18 x 12 = 216W

second line would be: 12 x 12 = 144

144 + 216 = 360

[tiro_uspsss]

if the PSU is advertised as a 2 line/rail PSU - then it is...
I recently bought a 2 line/rail PSU; I tried to power a large number of HDDs *&* a GPU of *one* 12V line/rail. result = unstable (HDDs were randomly powering down while in windows :down: ).
I then powered the GPU with the second line/rail, result = stable

[jonnyGURU]

My PSU have one 12V lane with 20A (+12V1) and a second lane with 18A (+12V2).

Will the PSU combine both lanes automaticly, when i need more then 20A ??
How can I get 30A from these PSU?

kind regards
Loopy

When they give you a "20A per rail (not "lane")" rating, they're just talking about the maximum capability any given connector can deliver. Because this is just a maximum per rail and not a claim of how much "+12V the PSU can actually produce, you can't just add the rails up to get your actual +12V capability.

As adamsleath points out, the important number is BELOW these two. You found that number to be "360W". 360W / 12V = 30A.

Is the power "available" if you need more than 20A on a connector? Well, you shouldn't ever need more than 20A on a connector because that would actually exceed the mechanical tolerances of any connector used in any PC made today (max is around 12A.)

Will having the two rails pose a problem? Depends on your rig. Typically when you have two +12V rails, one rail goes to the CPU and the other goes to everything else. For some higher end rigs, like one with a couple 8800 GTX cards, there could be a problem. But for anyone to offer an educated opinion on how this PC will fair in your system.. yeah, we need to know all your specs.