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So does point 1) mean that it takes too much energy to run a faster CPU, because power is always leaking away?

Also curious--are transistors small enough now that they can experience weird quantum effects?




No, point 1 means that 'active' power (which is the power the system dissipates when it is actively switching things) limits the maximum clock rate. Higher clock rate, more heat is generated, heat can't get out of the chip fast enough so chip temperature rises, transistors fail.

Leakage current, that is to say the current that flows through transistors because they cannot be fully turned 'off' is a sort of power 'floor.' If you use the 'water flowing' model of heat transfer (its not useful for simulation but it can explain behaviors) the leakage current results in a fixed amount of heat being dumped into the chip. Active power dissipation gets added to that and the combination is the total power created. Chip designers build systems to transfer that heat into an ambient cooling fluid (typically air) and away from the chip. You can do that by blowing air over a large surface area (as room temperature air goes by, it becomes warmer and the heat sink becomes cooler).

The transistors have always been small enough for 'weird quantum effects' the most well known is quantum tunneling of electrons into the gate area. Those effects are known and designed around but so far have not prevented the shrinkage of transistors (increasing the areal density of same).




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