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A comment on The cooling advantage that CPU integrated graphics has. Parent comment

Re:The cooling advantage that CPU integrated graphics has by mschuster91 on Friday January 26, 2024 @08:32AM (#39142405)
The distance that this kind of amperage has to flow through is very small, meaning that the resistance along the path isn't that bad.

PCIe traces however run 10x (or more) the distance, so heat dissipation is more of a concern there.

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Re:The cooling advantage that CPU integrated graphics has by timw4mail on Friday January 26, 2024 @08:50AM (#39142553)
The distance is larger than you think, but it is spread over a lot of pins. Most of the pins on a CPU are for power and ground.
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Re:The cooling advantage that CPU integrated graphics has by pwg on Friday January 26, 2024 @01:02PM (#39145651)
> The distance that this kind of amperage has to flow through is very small, meaning that the resistance along the path isn't that bad.

The formula for resistive wattage dissipation does not include "distance" in it.

The formula is i^2r (i squared times r) where i is current and r is resistance.

So 10 amps flowing through 2 ohms dissipates 200 watts, and it does not matter if the "2 ohms" is 1mm long or 1m long.

So what matters is the net resistance of that short distance, not the distance itself.

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