⚡ Undervolting ⚡

Benefits of undervolting

Lower power consumption P = I * V
Higher performance when power limits engaged, the CPU require less power to reach higher clocks.
Lower thermals due to less generated heat, preventing thermal throttle
Quieter fan noise
Longer battery life due to lower power consumption

Guides

Explanation

Components have a margin of error in terms of stability. Manufacturers push more voltage in than needed in order to make sure they're stable.

For example, suppose a CPU needs 1 volt in order to perform its tasks. If the CPU gets less than 1v, then it will become unstable and not be able to perform its task because it doesn't have enough power to do so. So (let's say Intel) Intel shoves 1.1v into the CPU to make sure it's stable. A slight overvolt will not hurt the CPU, but it will increase the heat output because it's running less efficiently now. The CPU is getting more power than it needs, so it's generating more heat for the same performance. This is where undervolting comes in

When undervolting, you the user is doing the work to find the stable point of your CPU in order to maximize its efficiency. The less unnecessary voltage you feed the CPU, the more efficient it can run (because again, it doesn't need to take in unnecessary power and consequently, heat). So by undervolting, you can feed this theoretical CPU exactly 1v or maybe 1.01v.

Why doesn't intel just feed the CPU 1v from the factory? well that's because every single CPU is very very slightly different, so the exact same CPU model might need 1.02v to be stable, and another might need 0.99v. By giving it 1.1v out of the box, it ensures that all these CPUs are stable, at the expense of lower efficiency.

Here's an example with my Dell laptop. I have an i5-7300HQ, and running aida64 without undervolting pulls about +25w of power. After a -150mv undervolt, I can run the same aida64 test at 18w of power. That means 7w less heat and power consumption.