Just an FYI note: I am sensitive to laptop heat issues, and I've been bothered for years about the fact that Linux runs significantly hotter (for me, typically about 10F outside case temperature) than Windows on the same laptop.

I looked into heat control when I decided to chuck my Solus Plasma Optiplex desktop and use my Latitude laptop full-time, connecting an external monitor and keyboard when I was using the laptop as a desktop.

I ran across thermald, an Intel daemon that replicates the power efficiencies of Intel components on
Windows (DTS, Intel P state driver, power clamp driver, CPUfreqcontrols and so on) in Linux. Thermald works by monitoring the thermal state of the laptop and applying Intel compensation methods to keep temperature low.

I installed thermald last week (thermald is in the repository), and have been monitoring case temperatures frequently since then. Result: Case temperatures dropped significantly when I am using the laptop under load.

Thermald works only with Intel. It won't work with AMD or NVIDIA CPU/GPU or third-party components. But on my Intel-only laptop, it seems to work well. As I said, just an FYI note.

    tomscharbach I installed thermald last week (thermald is in the repository)

    Good catch!

    Is installation all that's needed, or is there more to it than that. Three of our four laptops here are Dells, thus Intel Inside. We're not experiencing any noticeable heat issues, but it sounds like a good idea regardless.

    EDIT: Actually four out of four of out laptops are Intel. Even the little Travelmate runs on a Celeron, with Intel components. I can't imagine its ever getting hot, though.

        WetGeek Is installation all that's needed, or is there more to it than that.

        As I understand it, you need to install and then start thermald with by typing the command "thermald" into the terminal. Once started, thermald starts on boot thereafter. You can apparently use the command line to set options and parameters, but I have not done so. I just let it run on default settings.

            tomscharbach As I understand it, you need to install and then start thermald with by typing the command "thermald" into the terminal.

            Yep. After I asked that, I checked out the --help information, and it agrees with you. There's an option to start it as a non-daemon, and a few other interesting options, but simply running it enables it and starts it as a daemon.

            Now I have something to do with all these laptops besides fretting over non-working VMs. It probablly wouldn't hurt anything to install it on my DELL media machine, though it's not a laptop. It's in use virtually 24/7.

                WetGeek Now I have something to do with all these laptops

                I just had an idea that seems to have worked out. During the pandemic I bought a good quality IR thermometer for frequently testing our foreheads. It happens that it works for my Latitude as well. When used to take a temperature at the top of the keyboard, it reports that it's 97.3 f there. I'll check again tomorrow, with thermald running, to see if it's done anything to cool this machine. Gonna reboot it now, and leave it running overnight, as usual.

                    WetGeek I bought a good quality IR thermometer ...

                    I use an IR thermometer to check case temperature, but I don't claim high quality. Works okay, I guess, regardless, because what counts is difference over time patterns, and the measurements don't need to be accurate to a tenth of a degree. A degree or so is fine.

                    Thanks to me you have an old toy to play with in a new way. Just like a good pre-school, hanging around me.

                        tomscharbach I use an IR thermometer to check case temperature

                        After reading for a while, I couldn't sleep, so I came back downstairs. The laptop, with 7 applications running, is now 7 degrees f lower than when I retired earlier. Granted, it's not under a lot of stress, but I am using it, and so far I'm pretty impressed with the difference.

                        At one time I knew of an applet that read temperature sensors and displayed them, but I've probably lost it now. I don't even remember the name, but maybe if I check the Plasma panel applets, I'll remember it.

                            WetGeek At one time I knew of an applet that read temperature sensors and displayed them, but I've probably lost it now. I don't even remember the name, but maybe if I check the Plasma panel applets, I'll remember it.

                            I didn't find anything in Plasma widgets, but the repository has the psensor package, which seems to fit the bill. I'm not planning on installing psensor because I won't use the information, the package adds 15-odd Gnome-ish dependencies, and monitoring adds operating overhead.

                            Thermald seems to be doing its job, though. The laptop runs cooler than it did. I've seen reviews from gamers that suggest that the external temperature runs 20-30 degrees F lower than it did, but that involves careful customization. Running it on auto/default settings, I think I'm running about 8-10 degrees F cooler, on average, than I did before Thermald. That's good enough.

                                tomscharbach I'm not planning on installing psensor because I won't use the information

                                Yeah, I agree. I wouldn't use it either. My Latitude seems to vary between about 91 degrees to 97 degrees, depending on how hard it's working. Right now, it's 92.4. I don't have a record of what that range was before I installed thermald, so I don't really have a good idea of what it's doing.

                                However, I'm sure that Intel knows what they're doing, so I'm not going to remove it from this laptop. I also don't plan to install it on the rest of the Intel machines here. I"m not convinced that any of them seems to need it.

                                By the way, there's a white LED that's lit on the F4 key of these Latitudes. I know that at one time it was turned off on mine, but I have no idea what I did to achieve that. Now that I've rebuilt this machine, it's on again, and I find it distracting. Any idea what it means, and how I might turn it off?

                                    WetGeek By the way, there's a white LED that's lit on the F4 key of these Latitudes. I know that at one time it was turned off on mine, but I have no idea what I did to achieve that. Now that I've rebuilt this machine, it's on again, and I find it distracting. Any idea what it means, and how I might turn it off?

                                    Yeah. I noticed this, too, in the last few days. Dell's support docs suggests that the F4 key stays lit when the microphone is disabled by the system:

                                    "On some Latitude systems the F4 key is used to mute the built in microphone. However if the Microphone is disabled in the BIOS the light will remain on after the system has booted into the Windows operating system. This is working as designed and the light remains on as an indication that it has been disabled in the system BIOS. To restore the functionality of the F4 key, re-enable the microphone in the BIOS."

                                    In my case, the F4 key lights up when I plug the laptop into an external docking station using the USB-C port. When plugged into the dock, the "volume" thingy on the taskbar does not show microphone volume. When the laptop is not plugged into the docking station, the F4 key light goes away and I can adjust microphone volume using the taskbar thingy. So, in my case, it seems to have to do with docking (external keyboard and HDMI monitor) turning off the microphone somehow. Odd.

                                    If you are not using a dock, you might check your BIOS to make sure that the microphone is enabled. If you are using a docking station, welcome to the club.

                                    I'll look into it and share what I find.

                                        tomscharbach If you are not using a dock, you might check your BIOS to make sure that the microphone is enabled

                                        Thanks for checking on that. I use the microphone on my Logitech HD camera, so I don't really want the internal mic turned on, but Whereby lets me choose from among available microphones when I use it for our family chats. I can just not choose the internal mic. And if it ever offends me otherwise, I guess I could just turn its volue down to 0.

                                          tomscharbach If you are not using a dock, you might check your BIOS to make sure that the microphone is enabled

                                          I checked the BIOS. The internal microphone was enabled, and still the LED was on. I turned the internal mic off, and rebooted, and still the LED was on. It doesn't seem to turn off regardless of what I do. Just to be sure, I'm going to turn it back on, and mute the internal microphone from the settings. Maybe that will do it.

                                              WetGeek I'm going to turn it back on, and mute the internal microphone from the settings. Maybe that will do it.

                                              I turned it off! In the BIOS it's enabled. In the System Settings the internal microphone must NOT be muted, but its volume can be set to the lowest level without actually muting it. Mute it, and the LED comes back on. Un-mute it, and the LED turns off.

                                              Since I don't use a dock, I was unable to test it there. Maybe you can use something from my results to turn it off on your system. It's really amazing how annoying one little useless LED can be.

                                                What does your speaker output look like? Mine, of all things, shows "Dummy Output" under "Inactive Devices" and I can't find a way to change it. I'm going into a number of Zoom meetings right now, and I hope that the speaker output actually works. If it doesn't, I'll swap to the Latitude 5520.

                                                  tomscharbach What does your speaker output look like

                                                  I didn't know if you wanted me to switch to inactive devices. This is what that shows.

                                                  Did you manage to get your F4 LED turned off whiile connected to the dock?

                                                    The F4 is fine. Thanks.

                                                    I've switched over to my portable "Plasma on a Stick" setup for the Zoom meetings, and I'll try to figure out what is going on with my in-laptop Plasma this afternoon. In a nutshell, the speakers don't show at all unless I click on "Inactive Devices" and then "Dummy Output" is what shows up. In a nutshell, my equivalent of your first screen is that it shows "Recording Devices" only (no "Speakers" shown at all) and my equivalent of the second screen shows "Dummy Output" under "Playback Devices".

                                                      tomscharbach In a nutshell, the speakers don't show at all unless I click on "Inactive Devices" and then "Dummy Output" is what shows up

                                                      Sorry to hear that. I noticed that when I checked the internal microphone in my BIOS, it was also possible to turn off the internal speakers. Is it possible that those got set to OFF somehow?

                                                          WetGeek I don't think so, but I did check. Both micorphone and speakers are enabled in BIOS. The fact that the speakers show up on my portable "Plasma on a Stick" build suggests that I screwed up something in my in-laptop build. What, I don't know.