On my laptop HP 8560W i have installed Windows 10 and Manjaro KDE. On Manjaro when i am watching youtube video the cpu temperature is around 65-70 degrees, on Windows when i watch the same youtube video the cpu temperature is around 50-55 degrees. On Manjaro when the system is idle the cpu temperature is around 50 degrees, on Windows when the system is idle the cpu temperature is around 40 degrees.
Does that mean Windows is better in managing cpu temperature?
If your question has āon your particular laptop by defaultā, then the answer might be yes. On other devices, it can be the other way around, like my ROG Strix GL503VD.
Otherwise, you should find out why first then start looking for solution afterwards.
Watching youtube -> Do you use the same browser? Is it Chrome? If yes then the browser might be the culprit at hardware accelerated video decoding isnāt enabled for Linux, courtesy of Google. If you use Chromium, however, I believe whatever version is availabe in the repo right now has it patched and enabled.
Idle time -> How do you measure idleness? 10Ā° is a rather large difference, so something must be running behind the scene. htop or similar utility should tell you if the CPU isnāt really on idle.
Iād imagine the culprit here is certainly hardware acceleration. Videos are decoded by the CPU instead of the GPU when hardware acceleration isnāt working.
You might also want to look at fan speeds, or whether they are on at all. 50 degrees idle is perfectly fine, it might even mean your laptop is quieter and more energy efficient at idle?
With my room temperature at 26 celcius, starting at 45C on my (non mobile) 65W i3-4130 processor - opening up Youtube in Chrome whilst still using Firefox did push it all the way up to 67 celcius. I use āxsensorsā to put the information on screen. Possibly relevant - I have no fluff in my system (itās an ATX with a 120mm fan pulling air in over 3 hard disks, and standard intel fan next to the exhaust fan at the backā¦).
Two points here:
There are different sensors, and itās easy to get the wrong temperature. For example, Temp1 39, Temp2 127, Temp3 34.
It would be worth monitoring the fan speed to see if that also correlates.
I get higher cpu temperature watching youtube videos when using Firefox and Brave. Hardware acceleration on Firefox is enabled. I am comparing idle temperatures when i donāt have applications opened.
I had other distros installed on the same laptop, mostly based on debian and ubuntu, and also fedora, and i had the same issues with all of them. I installed Manjaro because it is based on Arch Linux to see if there will be any improvement, but there is not. My conclusion is that Windows is just superior in managing cpu temperatures.
Yeah, Video HW accel support is there, but that does not mean it is being utilized. Depending on the GPU it might needs some tweaks/settings to be enabled:
https://wiki.archlinux.org/index.php/chromium#Hardware_video_acceleration
That does not neccesarilly mean VIDEO decoding is gpu accelerated as well though.
https://wiki.archlinux.org/index.php/Hardware_video_acceleration
Firefox:
https://wiki.archlinux.org/index.php/Firefox#Hardware_video_acceleration
Now even if you got everything configured correctly, some video codecs might not be supported to be decoded by your GPU (see vainfo output). There are some addons forcing certain codecs to be used (if available, eg youtube) like h264ify.
Look what is happening with cpu temperature just by scrolling up and down web page in firefox. It jumps with 30 degrees. This canāt be normal.
https://imgur.com/a/0U52dV1
Firefox has most of Linux graphics drivers blacklisted for GPU acceleration. So your browser is using your CPU a lot. This is normal. I am using Radeon 5700 XT and tried to enable WebRenderer on Manjaro but that caused freezes, so I backed down.
Windows graphics drivers on the other hand work fine with all browsers with acceleration. Thatās why you have lower temperatures.
Btw.: Are you comparing the same sensors?
Manjaro might show the sensor from the CPU core/DIE (usually the highest one of the different cores) and windows might show the socket temperature instead.
The temperature values from the individual cores are fluctuating much more and raise much faster since they are much closer to where the heat is generated. When you stop scrolling your should see the temp dropping real quick againā¦ Due to the slim design of laptops in general, their cooling solutions are much worse compared to desktop machines and heat cannot be dissipated that quick.
Anyways as @cryptocurious already mentioned GPU acceleration for rendering might be blacklisted for certain GPUās. You could try playing around with some settings like force enabling WebRender and WebGL in the browser configā¦ If you are lucky and it works flawlessly that should help offloading rendering work to the GPU (which will in turn reduce power consumption and thus produce less heat)
I run sensors-detect but it detected only one module. Is that normal? I press Enter to all question. This is the output:
# sensors-detect version 3.6.0
# System: Hewlett-Packard HP EliteBook 8560w [A0001D02] (laptop)
# Board: Hewlett-Packard 1631
# Kernel: 5.10.2-2-MANJARO x86_64
# Processor: Intel(R) Core(TM) i7-2820QM CPU @ 2.30GHz (6/42/7)
This program will help you determine which kernel modules you need
to load to use lm_sensors most effectively. It is generally safe
and recommended to accept the default answers to all questions,
unless you know what you're doing.
Some south bridges, CPUs or memory controllers contain embedded sensors.
Do you want to scan for them? This is totally safe. (YES/no):
Silicon Integrated Systems SIS5595... No
VIA VT82C686 Integrated Sensors... No
VIA VT8231 Integrated Sensors... No
AMD K8 thermal sensors... No
AMD Family 10h thermal sensors... No
AMD Family 11h thermal sensors... No
AMD Family 12h and 14h thermal sensors... No
AMD Family 15h thermal sensors... No
AMD Family 16h thermal sensors... No
AMD Family 17h thermal sensors... No
AMD Family 15h power sensors... No
AMD Family 16h power sensors... No
Hygon Family 18h thermal sensors... No
Intel digital thermal sensor... Success!
(driver `coretemp')
Intel AMB FB-DIMM thermal sensor... No
Intel 5500/5520/X58 thermal sensor... No
VIA C7 thermal sensor... No
VIA Nano thermal sensor... No
Some Super I/O chips contain embedded sensors. We have to write to
standard I/O ports to probe them. This is usually safe.
Do you want to scan for Super I/O sensors? (YES/no):
Probing for Super-I/O at 0x2e/0x2f
Trying family `National Semiconductor/ITE'... No
Trying family `SMSC'... Yes
Found unknown chip with ID 0x0701
Probing for Super-I/O at 0x4e/0x4f
Trying family `National Semiconductor/ITE'... No
Trying family `SMSC'... Yes
Found `SMSC LPC47N217 Super IO'
(no hardware monitoring capabilities)
Some hardware monitoring chips are accessible through the ISA I/O ports.
We have to write to arbitrary I/O ports to probe them. This is usually
safe though. Yes, you do have ISA I/O ports even if you do not have any
ISA slots! Do you want to scan the ISA I/O ports? (YES/no):
Probing for `National Semiconductor LM78' at 0x290... No
Probing for `National Semiconductor LM79' at 0x290... No
Probing for `Winbond W83781D' at 0x290... No
Probing for `Winbond W83782D' at 0x290... No
Lastly, we can probe the I2C/SMBus adapters for connected hardware
monitoring devices. This is the most risky part, and while it works
reasonably well on most systems, it has been reported to cause trouble
on some systems.
Do you want to probe the I2C/SMBus adapters now? (YES/no):
Sorry, no supported PCI bus adapters found.
Module i2c-dev loaded successfully.
Next adapter: NVIDIA i2c adapter 0 at 1:00.0 (i2c-0)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 1 at 1:00.0 (i2c-1)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 2 at 1:00.0 (i2c-2)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 3 at 1:00.0 (i2c-3)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 5 at 1:00.0 (i2c-4)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 6 at 1:00.0 (i2c-5)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 7 at 1:00.0 (i2c-6)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 8 at 1:00.0 (i2c-7)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 9 at 1:00.0 (i2c-8)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 13 at 1:00.0 (i2c-9)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 12 at 1:00.0 (i2c-10)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 11 at 1:00.0 (i2c-11)
Do you want to scan it? (yes/NO/selectively):
Next adapter: NVIDIA i2c adapter 10 at 1:00.0 (i2c-12)
Do you want to scan it? (yes/NO/selectively):
Now follows a summary of the probes I have just done.
Just press ENTER to continue:
Driver `coretemp':
* Chip `Intel digital thermal sensor' (confidence: 9)
Do you want to overwrite /etc/conf.d/lm_sensors? (YES/no):
Unloading i2c-dev... OKLooks like KDE ā¦ are you using opengl or xrender ?
https://userbase.kde.org/Desktop_Effects_Performance#OpenGL_Version
I donāt think KDE is the issue. I have installed other distros with different desktop environment and had the same problem with high cpu temperature.
I already replied to you. All Linux distros share same issue, disabled hardware acceleration in browsers comparing to excellent and matured support in Windows.
You canāt fix it, unless you want to play with experimental features, you can force-enable acceleration but results and stability is not guaranteed.
Got it. Then, i guess, Windows 10 will stay my primary OS.
You decide to stay on Windows because your CPU sensor shows higher temperature? 
It doesnāt just show hotter temperature, the laptop becomes hotter. And the fan is activating more often, which is kind of annoying. The other issue is that display scaling in linux is still not good enough.
Well thatās one solution, I wouldnāt ditch Windows until I could make Linux work properly for my hardware.
It would be good to look at cpufreq too, have a conky showing cpu temp and fan speed, but really this sh1t should just work shouldnāt it?
I guess Iām lucky, with a simple i3-4130 I enabled Firefox gfx and got away with itā¦ also not such an issue with a full ATX case with in/out fans mostly to cool hard drives, running a low power system.
Looking at the specs of your computer it has a dedicated GPU and probably you are not using the optimal driver for it. Take a look at this:
https://wiki.manjaro.org/index.php/Configure_Graphics_Cards
Hoy can also try disabling the dGPU in the BIOS, some laptops allow that. Iām sure the GPU is the source of your high temperatures.
This is the gpu driver i have installed:
Graphics: Device-1: NVIDIA GF108GLM [Quadro 1000M] driver: nvidia v: 390.138
Device-2: IMC Networks USB2.0-Camera type: USB driver: uvcvideo
Display: server: X.Org 1.20.10 driver: nvidia resolution: 1920x1080~60Hz
OpenGL: renderer: llvmpipe (LLVM 11.0.0 256 bits) v: 4.5 Mesa 20.3.1My laptop has an nVidia GPU (970M) but I keep it disabled in the BIOS, Iāll enable it and test different driver combinations and monitor temps. Ok let you know. Keep in mind that my GPU may behave very differently since it newer and probably is supported by the latest non-free drivers, in your case you have to use an old driver.