how are the 2 12v rails split up on a psu?

[tickle me elmo]

how are they shared so everything gets enough power? they dont give like the atx connector 10a and all other leads 15a does it ??

 

[Joe42]

Just asked this question in my thread. I'm also interested to find out how they work.

As far as i know its two mini 12v psu's with some circuitry to combine the power, as this is cheaper and easier. However why can't they deliver maximum power when combined?

Tagan psu's have a switch to split/combine the rails, what does this actually do?
Are they then split between wires rather than shared?

 

[fornowagain]

In general there is one 12v source. To which is connected two over current limit circuits. These are set to 240VA or 20A maximum. All it does is protect the wiring and the user from pulling to much current from one feed. Now they label the maximum a rails can supply say 2 x 18A. So each could go to 18A (20 really) but only one to the max at a time. The limit is the maximum wattage the 12v source can supply. You can't get more out than you put in. Say the maximum wattage is 360W that's 30A. 15A each, or 10A and 20A(which is the max). The tagan split rail, just takes out the over current limiter, so its all 36A in one rail

 

[Energize]

1 rail is solely for the cpu the other rail is for everything else. Quad rail psus are avalible as well.

 

[fornowagain]

1 rail is solely for the cpu the other rail is for everything else. Quad rail psus are avalible as well.

12v2 is supposed to be for the CPU. But not all the manufacturers stick to that spec.