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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: 0.227s | source
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ycui1986 ◴[18 Jun 24 06:42 UTC] No.40714732[source]▶
In 2006, I had my first laptop right before the release of Windows Vista. Unfortunately, running Windows Vista makes my laptop hot and the fan kicked in to make a lot noise. I cannot remember the software's name which can reduce the core voltage of my single core Centrino processor. I was successful to undervolt the CPU to the lowest possible voltage. That cools down the CPU by a large margin, the laptop became quiet again (also stable). I was happy. The functionality disappears with the newer generation intel CPU releases, I had not been able to do similar thing ever since.

Back then, Intel had the best semiconductor process, and they had a wide margin on undervolting the CPU.

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LoganDark ◴[18 Jun 24 12:18 UTC] No.40716916[source]▶
> The functionality disappears with the newer generation intel CPU releases, I had not been able to do similar thing ever since.

I don't know about undervolting, but ThrottleStop allowed me to run my 230W laptop off a 65W power adapter by downclocking the CPU to 800MHz!

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juujian ◴[18 Jun 24 13:42 UTC] No.40717772[source]▶
Did I get that right? A laptop that needs a 230W power brick and wasn't really intended to run on 65W, though it does? 800MHz, that was what we had in the 90s, I assume that's the era? Meanwhile, my laptop is idlying at ~9W playing YouTube. Crazy.

How long did the battery last? Less than 30m I assume.

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1. LoganDark ◴[18 Jun 24 14:02 UTC] No.40718000[source]▶
The laptop is designed to accept power over some terrible barrel jack that isn't actually made of metal. The conductive coating can scrape off after just a couple months of use and render it completely inert. That had happened again so I was stuck with USB-C charging, and that particular laptop only supported up to 65W via its single Thunderbolt port. I eventually fixed this for good by just stripping the barrel off and hard soldering the power cable directly to the motherboard.

Anyway, indeed, that laptop was not designed to run off 65W. Mainly because it had a dedicated Nvidia GPU, but also because it had a bunch of other stuff (couple 6W fans, bright 4K panel, etc.).

The battery basically didn't exist from the very day I got the laptop brand new from Best Buy. I'm not sure if it's possible to get good battery life out of a 99Wh battery while pulling 230W. Of course, you could simply increase the battery capacity, but a not-insignificant fraction of laptop buyers want to bring them on planes so that'd be a pretty dumb idea.