How to view thermal information in Linux

Linux kernel uses /sys subsystem to store and communicate system information and states. Temperature informations could also be obtained from the subsystem, with the caveat that the information is not in standard location and format as it differs between hardware models/manufacturers and its associated kernel module.

lm-sensors via libsensors try to address the issue by mapping these informations into an easily accessible interface for other programs to read and configure the values. It also provides userland tools for finding and reporting these values.

You can use lm-sensors to view information such as CPU and overall system temperature in Linux at the terminal.

1. Launch your preferred terminal application.
2. Install lm-sensors for your system.

   $ sudo pacman -S lm_sensors # Mint
   $ sudo yum install --assumeyes lm_sensors #Red Hat, CentOS
   $ sudo dnf install lm_sensors # Fedora
   $ sudo apt update && sudo apt install --assume-yes lm-sensors #Ubuntu, Debian
   $ sudo zypper in sensors #SUSE

3. Probe available sensors in your system using sensors-detect.

   $ sudo sensors-detect --auto
   # sensors-detect revision $Revision$
   # System: Dell Inc. Latitude E5470 (laptop)
   # Board: Dell Inc. 0VHKV0
   # Kernel: 5.0.0-20-generic x86_64
   # Processor: Intel(R) Core(TM) i5-6300U CPU @ 2.40GHz (6/78/3)
   
   Running in automatic mode, default answers to all questions
   are assumed.
   
   Some south bridges, CPUs or memory controllers contain embedded sensors.
   Do you want to scan for them? This is totally safe. (YES/no):
   Module cpuid loaded successfully.
   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
   Intel digital thermal sensor...                             Success!
       (driver `coretemp')
   ##### snipped
   Client found at address 0x52
   Probing for `Analog Devices ADM1033'...                     No
   Probing for `Analog Devices ADM1034'...                     No
   Probing for `SPD EEPROM'...                                 Yes
       (confidence 8, not a hardware monitoring chip)
   
   Next adapter: i915 gmbus dpc (i2c-1)
   Do you want to scan it? (yes/NO/selectively):
   
   Next adapter: i915 gmbus dpb (i2c-2)
   Do you want to scan it? (yes/NO/selectively):
   
   Next adapter: i915 gmbus dpd (i2c-3)
   Do you want to scan it? (yes/NO/selectively):
   
   Next adapter: DPDDC-A (i2c-4)
   Do you want to scan it? (yes/NO/selectively):
   
   Next adapter: DPDDC-C (i2c-5)
   Do you want to scan it? (yes/NO/selectively):
   
   
   Now follows a summary of the probes I have just done.
   
   Driver `coretemp':
     * Chip `Intel digital thermal sensor' (confidence: 9)
   
   To load everything that is needed, add this to /etc/modules:
   #----cut here----
   # Chip drivers
   coretemp
   #----cut here----
   If you have some drivers built into your kernel, the list above will
   contain too many modules. Skip the appropriate ones!
   
   Do you want to add these lines automatically to /etc/modules? (yes/NO)
   
   Unloading cpuid... OK

4. Start lm-sensors service if it's not already started (optional).

   $ sudo systemctl start lm-sensors

5. Configure lm-sensors service to automatically start during system boot.

   $ sudo systemctl enable lm-sensors
   Synchronizing state of lm-sensors.service with SysV service script with /lib/systemd/systemd-sysv-install.
   Executing: /lib/systemd/systemd-sysv-install enable lm-sensors

6. View temperature information for your system.

   $ sensors
   iwlwifi-virtual-0
   Adapter: Virtual device
   temp1:        +32.0°C
   
   pch_skylake-virtual-0
   Adapter: Virtual device
   temp1:        +33.0°C
   
   acpitz-acpi-0
   Adapter: ACPI interface
   temp1:        +25.0°C  (crit = +107.0°C)
   
   coretemp-isa-0000
   Adapter: ISA adapter
   Package id 0:  +34.0°C  (high = +100.0°C, crit = +100.0°C)
   Core 0:        +34.0°C  (high = +100.0°C, crit = +100.0°C)
   Core 1:        +34.0°C  (high = +100.0°C, crit = +100.0°C)
   
   dell_smm-virtual-0
   Adapter: Virtual device
   Processor Fan:    0 RPM
   CPU:            +34.0°C
   Ambient:        +31.0°C
   SODIMM:         +33.0°C
   Other:          +32.0°C

   Harddrive temperature information is not available via lm-sensors but could be viewed using hddtemp.
   How to view harddrive temperature in Linux

7. Install GUI applications or applets for your desktop environment (optional).

   • GNOME Sensors Applet
   • PowerTOP
   • psensor
   • s-tui