To put it simpily, for every inlet of power you need a outlet of equal carrying capacity,

No, that shows a misunderstanding of the term power.

Power is

**dissipated** in circuit elements. That power dissipated is calculable--it's the product of the current through the element and the voltage across the element.

Let's work an example.

To keep this easy, let's have you wire a 100 ohm resistor across the red and black wires on your molex connector. We know the red wire is +5V with respect to ground, so we have the voltage across the resistor: 5V. We can easily calculate the current through the resistor: V= I*R, so I = V/R = 5V/100 ohms = 0.05 A. Now we can calculate the power dissipated in that resisotr: P= V * I = 5V * 0.05A = 0.25W.

That quarter of a watt isn't "returned" to the PSU, it's converted to heat by the resistor. That's where your statement goes wrong.

If you had said the

**current** flowing in equals the

**current** flowing out, that would have been okay. But power and current are quite different.