So, there have been numerous reports around the internet that the HP ProBook 4510s has fan speed issues.
In my case, the following happens:
- Turn on the laptop: no problem.
- Using the laptop while on AC: no problem.
- Switch on the laptop from suspend mode without AC plugged in: problem!
The fan goes into overdrive and stays there.
It's related to the temperature measurements, somehow. According to the
sensors(1) tool, it's the
temp6 value that's off.
label temp6 "the-problem"
When I fire it up from suspend mode it's supposedly very high:
the-problem: +90.0°C (crit = +110.0°C)
It looks a bit like problem that's mentioned here: Re: Probook 4530s fan noise : DSDT table edition ? Although that post concerns the 4530s and other models.
I also found tools to edit the HP 4530s fan runtime state — 4530s.zip — but those don't fix the problem on the HP 4510s.
Finally I found a usable workaround: CPU load!
I hacked together a little script tries to burn a lot of CPU at once,
and believe it or not, the fan slows down immediately. As soon as your
hear that, hit
^C to exit the script.
I've noticed that the time it takes to work varies. Once it took a full minute. Sometimes it's done in seconds.