I mistakenly deleted the email below from the moderation queue. Fortunately I still had the original moderation notice. As such, I am sending this over to the ML.
@Php4fan -- I apologise. I am not sure if there was more to your email, so please verify. ..hggdh.. ---------- Forwarded message ---------- From: php fan <php4...@gmail.com> To: Ubuntu Quality Team <ubuntu-quality@lists.ubuntu.com> Cc: Bcc: Date: Tue, 21 Jul 2020 19:20:37 +0200 Subject: URGENT: I need a workaround or fix to the broken fan speed control Hello, As was reported years ago, there's a bug somewhere in Ubuntu that prevents the cooling fan to spin at the needed speed. The details are at https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1697567 but in a nutshell, the proof that something is wrong is that (a) my CPU gets so hot that it switches itself off, and (b) the fan doesn't get even remotely close to its maximum speed (or half that) when that happens. (a) and (b) are incompatible on a system that works, regardless of how bad a condition the fan may be in. If (a) happens, then the fan must by definition be spinning at its highest possible speed. If (b) is true (i.e. the fan is spinning at a much lower spin), then the temperature must be well below the safety value, otherwise the fan would be spinning faster in an attempt to cool it down. Recently the situation got worse, in two ways: 1. my CPU just gets hotter and it happens more often that it gets too hot. This *might* be due not to something having changed in how the software controls the speed: it could be that my fan has got more dirty and less efficient, and since the OS's way of controlling it fails to react properly, in the exact same way it always did, the situation is worse. But also: 2. when I reboot, it used to be the case that while Grub displayed the boot menu, the fan would start to spin much faster (proving that it is capable to, and that it needed to), and only later during the boot would it slow down (presumably because the broken speed control would kick in). Now, it spins too slowly even during the boot menu. The only explanation I can find for it is that the same broken speed control (or a different one equally or more broken) has now been implemented in Grub too. This means that I no longer even have at my disposal the last-resort pathetic workaround of restarting the machine and leaving it with the boot menu open to cool down for a few minutes before I resume working. By the way I recently upgraded from 16.04 to 20.04 and this hasn't been fixed. I observed the worsening in (1) before I upgraded (so either it has nothing to do with changes in software, or it was due to a software update in 16.04). On the other hand, the change (2) has happened while I was already using 20.04. I think that happened when I installed KDE Plasma Desktop, which installed something grub-related. Since nobody seems to care to fix a bug that has been known to brick computers for years, I urgently need a workaround to manually force my fan to spin faster. A. Is there a tool to manually control the fan speed? B. The speed control algorithm seems to be (the observed behavior suggests) a stupid temperature->speed map with no feedback or calibration whatsoever. Is this map stored somewhere in some file that I can edit, so I can try to simply increase the values of speed or decrease the threshold temperatures? Or is it hard-coded? -- Ubuntu-quality mailing list Ubuntu-quality@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-quality
