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Intel-undervolt: CPU undervolting and throttling configuration tool for Linux

(github.com)
132 points cl3misch | 1 comments | 17 Jun 24 22:44 UTC | HN request time: 0.207s | source
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hu3 ◴[18 Jun 24 14:26 UTC] No.40718245[source]▶
I slightly undervolted an i7 11800H by -100mV.

That resulted in a -10C average CPU temperature. Massive!

I don't remember last time I heard the fans. Not even with Docker + Jetbrains IDEs.

I wonder why doesn't it come like this by default. It runs faster too because it's no longer frequently thermal throttled.

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atVelocet ◴[18 Jun 24 15:00 UTC] No.40718594[source]▶
Cause the CPU can get unstable under certain loads. So Intel plays it safe and ramps up the voltage. And no.. there is no easy way to measure this. Also every CPU is slightly different.
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rcthompson ◴[18 Jun 24 15:13 UTC] No.40718737[source]▶
It's not just unstable, it's a security issue because control over CPU voltage allows someone to use that instability to compromise computations that are supposed to be performed securely (e.g. look up "Plundervolt").
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1. epcoa ◴[18 Jun 24 20:55 UTC] No.40722131[source]▶
If plundervolt is a viable attack you’ve got much bigger problems (the attacker must already have gained full privileges). Not sure how this is relevant to just using throttled or similar to conditionally undervolt the CPU with fixed levels that can be proven reasonably stable.