Related articles * [Fan speed control](/index.php/Fan_speed_control "Fan speed control") * [hddtemp](/index.php/Hddtemp "Hddtemp") * [monitorix](/index.php/Monitorix "Monitorix") [lm_sensors](http://lm-sensors.org/) (Linux monitoring sensors) is a free and open-source application that provides tools and drivers for monitoring temperatures, voltage, and fans. This document explains how to install, configure, and use lm_sensors. ## Contents * [1 Installation](#Installation) * [2 Setup](#Setup) * [3 Running sensors](#Running_sensors) * [3.1 Reading SPD values from memory modules (optional)](#Reading_SPD_values_from_memory_modules_.28optional.29) * [4 Using sensor data](#Using_sensor_data) * [4.1 Graphical front-ends](#Graphical_front-ends) * [4.2 sensord](#sensord) * [5 Tips and tricks](#Tips_and_tricks) * [5.1 Adjusting values](#Adjusting_values) * [5.1.1 Example 1\. Adjusting temperature offsets](#Example_1._Adjusting_temperature_offsets) * [5.1.2 Example 2\. Renaming labels](#Example_2._Renaming_labels) * [5.1.3 Example 3\. Renumbering cores for multi-CPU systems](#Example_3._Renumbering_cores_for_multi-CPU_systems) * [5.2 Automatic lm_sensors deployment](#Automatic_lm_sensors_deployment) * [6 Troubleshooting](#Troubleshooting) * [6.1 K10Temp module](#K10Temp_module) * [6.2 Asus Z97/Z190 motherboards](#Asus_Z97.2FZ190_motherboards) * [6.3 Gigabyte GA-J1900N-D3V](#Gigabyte_GA-J1900N-D3V) * [6.4 Laptop screen issues after running sensors-detect](#Laptop_screen_issues_after_running_sensors-detect) ## Installation [Install](/index.php/Install "Install") the [lm_sensors](https://www.archlinux.org/packages/?name=lm_sensors) package. **Note:** More documentation is at the [GitHub repository](https://github.com/groeck/lm-sensors/tree/master/doc). In the future these may be installed, see [FS#48354](https://bugs.archlinux.org/task/48354). ## Setup Use *sensors-detect* as root to detect and generate a list of kernel modules: **Warning:** Do not use anything other than the default options (by just hitting `Enter`), unless you know exactly what you are doing. See [#Laptop screen issues after running sensors-detect](#Laptop_screen_issues_after_running_sensors-detect). ``` # sensors-detect ``` It will ask to probe for various hardware. The "safe" answers are the defaults, so just hitting `Enter` to all the questions will generally not cause any problems. This will create the `/etc/conf.d/lm_sensors` configuration file which is used by `lm_sensors.service` to automatically load kernel modules on boot. When the detection is finished, a summary of the probes is presented. Example: `# sensors-detect` ``` 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): 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 ... 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) Driver `lm90': * Bus `SMBus nForce2 adapter at 4d00' Busdriver `i2c_nforce2', I2C address 0x4c Chip `Winbond W83L771AWG/ASG' (confidence: 6) Do you want to overwrite /etc/conf.d/lm_sensors? (YES/no): ln -s '/usr/lib/systemd/system/lm_sensors.service' '/etc/systemd/system/multi-user.target.wants/lm_sensors.service' Unloading i2c-dev... OK Unloading cpuid... OK ``` **Note:** A systemd service is automatically enabled if users answer **YES** when asked about generating `/etc/conf.d/lm_sensors`. Answering **YES** also automatically starts the service. ## Running sensors Example running `sensors`: `$ sensors` ``` coretemp-isa-0000 Adapter: ISA adapter Core 0: +35.0°C (crit = +105.0°C) Core 1: +32.0°C (crit = +105.0°C) w83l771-i2c-0-4c Adapter: SMBus nForce2 adapter at 4d00 temp1: +28.0°C (low = -40.0°C, high = +70.0°C) (crit = +85.0°C, hyst = +75.0°C) temp2: +37.4°C (low = -40.0°C, high = +70.0°C) (crit = +110.0°C, hyst = +100.0°C) ``` ### Reading SPD values from memory modules (optional) To read the SPD timing values from memory modules, install the [i2c-tools](https://www.archlinux.org/packages/?name=i2c-tools) package. Once installed, load the `eeprom` [kernel module](/index.php/Kernel_module "Kernel module"). ``` # modprobe eeprom ``` Finally, view memory information with `decode-dimms`. Here is partial output from one machine: `# decode-dimms` ``` Memory Serial Presence Detect Decoder By Philip Edelbrock, Christian Zuckschwerdt, Burkart Lingner, Jean Delvare, Trent Piepho and others Decoding EEPROM: /sys/bus/i2c/drivers/eeprom/0-0050 Guessing DIMM is in bank 1 ---=== SPD EEPROM Information ===--- EEPROM CRC of bytes 0-116 OK (0x583F) # of bytes written to SDRAM EEPROM 176 Total number of bytes in EEPROM 512 Fundamental Memory type DDR3 SDRAM Module Type UDIMM ---=== Memory Characteristics ===--- Fine time base 2.500 ps Medium time base 0.125 ns Maximum module speed 1066MHz (PC3-8533) Size 2048 MB Banks x Rows x Columns x Bits 8 x 14 x 10 x 64 Ranks 2 SDRAM Device Width 8 bits tCL-tRCD-tRP-tRAS 7-7-7-33 Supported CAS Latencies (tCL) 8T, 7T, 6T, 5T ---=== Timing Parameters ===--- Minimum Write Recovery time (tWR) 15.000 ns Minimum Row Active to Row Active Delay (tRRD) 7.500 ns Minimum Active to Auto-Refresh Delay (tRC) 49.500 ns Minimum Recovery Delay (tRFC) 110.000 ns Minimum Write to Read CMD Delay (tWTR) 7.500 ns Minimum Read to Pre-charge CMD Delay (tRTP) 7.500 ns Minimum Four Activate Window Delay (tFAW) 30.000 ns ---=== Optional Features ===--- Operable voltages 1.5V RZQ/6 supported? Yes RZQ/7 supported? Yes DLL-Off Mode supported? No Operating temperature range 0-85C Refresh Rate in extended temp range 1X Auto Self-Refresh? Yes On-Die Thermal Sensor readout? No Partial Array Self-Refresh? No Thermal Sensor Accuracy Not implemented SDRAM Device Type Standard Monolithic ---=== Physical Characteristics ===--- Module Height (mm) 15 Module Thickness (mm) 1 front, 1 back Module Width (mm) 133.5 Module Reference Card B ---=== Manufacturer Data ===--- Module Manufacturer Invalid Manufacturing Location Code 0x02 Part Number OCZ3G1600LV2G ... ``` ## Using sensor data ### Graphical front-ends There are a variety of front-ends for sensors data. * **psensor** — GTK+ application for monitoring hardware sensors, including temperatures and fan speeds. Monitors motherboard and CPU (using lm-sensors), Nvidia GPUs (using XNVCtrl), and harddisks (using [hddtemp](/index.php/Hddtemp "Hddtemp") or libatasmart). [https://wpitchoune.net/psensor/](https://wpitchoune.net/psensor/) || [psensor](https://www.archlinux.org/packages/?name=psensor) * **xsensors** — X11 interface to lm_sensors. [http://linuxhardware.org/xsensors/](http://linuxhardware.org/xsensors/) || [xsensors](https://www.archlinux.org/packages/?name=xsensors) For specific [Desktop environments](/index.php/Desktop_environments "Desktop environments"): * **Freon (GNOME Shell extension)** — Extension for displaying CPU temperature, disk temperature, video card temperature , voltage and fan RPM in [GNOME](/index.php/GNOME "GNOME") Shell. [https://github.com/UshakovVasilii/gnome-shell-extension-freon](https://github.com/UshakovVasilii/gnome-shell-extension-freon) || [gnome-shell-extension-freon](https://aur.archlinux.org/packages/gnome-shell-extension-freon/) * **GNOME Sensors Applet** — Applet for the [GNOME](/index.php/GNOME "GNOME") Panel to display readings from hardware sensors, including CPU temperature, fan speeds and voltage readings. [http://sensors-applet.sourceforge.net/](http://sensors-applet.sourceforge.net/) || [sensors-applet](https://www.archlinux.org/packages/?name=sensors-applet) * **lm-sensors (LXPanel plugin)** — Monitor temperature/voltages/fan speeds in [LXDE](/index.php/LXDE "LXDE") through lm-sensors. [http://danamlund.dk/sensors_lxpanel_plugin/](http://danamlund.dk/sensors_lxpanel_plugin/) || [sensors-lxpanel-plugin](https://aur.archlinux.org/packages/sensors-lxpanel-plugin/) * **MATE Sensors Applet** — Display readings from hardware sensors in your [MATE](/index.php/MATE "MATE") panel. [https://github.com/mate-desktop/mate-sensors-applet](https://github.com/mate-desktop/mate-sensors-applet) || [mate-sensors-applet](https://www.archlinux.org/packages/?name=mate-sensors-applet) * **Sensors (Xfce4 panel plugin)** — Hardware sensors plugin for the [Xfce](/index.php/Xfce "Xfce") panel. [http://goodies.xfce.org/projects/panel-plugins/xfce4-sensors-plugin](http://goodies.xfce.org/projects/panel-plugins/xfce4-sensors-plugin) || [xfce4-sensors-plugin](https://www.archlinux.org/packages/?name=xfce4-sensors-plugin) * **Thermal Monitor (Plasma 5 applet)** — [KDE](/index.php/KDE "KDE") Plasma applet for monitoring CPU, GPU and other available temperature sensors. [https://github.com/kotelnik/plasma-applet-thermal-monitor](https://github.com/kotelnik/plasma-applet-thermal-monitor) || [plasma5-applets-thermal-monitor-git](https://aur.archlinux.org/packages/plasma5-applets-thermal-monitor-git/) ### sensord There is an optional daemon called sensord (included with the [lm_sensors](https://www.archlinux.org/packages/?name=lm_sensors) package) which can log data to a round robin database (rrd) and later visualize graphically. See the sensord man page for details. ## Tips and tricks ### Adjusting values In some cases, the data displayed might be incorrect or users may wish to rename the output. Use cases include: * Incorrect temperature values due to a wrong offset (i.e. temps are reported 20 °C higher then actual). * Users wish to rename the output of some sensors. * The cores might be displayed in an incorrect order. All of the above (and more) can be adjusted by overriding the package provides settings in `/etc/sensors3.conf` by creating `/etc/sensors.d/foo` wherein any number of tweaks will override the default values. It is recommended to rename 'foo' to the motherboard brand and model but this naming nomenclature is optional. **Note:** Do not edit /etc/sensors3.conf directly since package updates will overwrite any changes thus losing them. #### Example 1\. Adjusting temperature offsets This is a real example on a Zotac ION-ITX-A-U motherboard. The coretemp values are off by 20 °C (too high) and are adjusted down to Intel specs. `$ sensors` ``` coretemp-isa-0000 Adapter: ISA adapter Core 0: +57.0°C (crit = +125.0°C) Core 1: +55.0°C (crit = +125.0°C) ... ``` Run `sensors` with the `-u` switch to see what options are available for each physical chip (raw mode): `$ sensors -u` ``` coretemp-isa-0000 Adapter: ISA adapter Core 0: temp2_input: 57.000 temp2_crit: 125.000 temp2_crit_alarm: 0.000 Core 1: temp3_input: 55.000 temp3_crit: 125.000 temp3_crit_alarm: 0.000 ... ``` Create the following file overriding the default values: `/etc/sensors.d/Zotac-IONITX-A-U` ``` chip "coretemp-isa-0000" label temp2 "Core 0" compute temp2 @-20,@-20 label temp3 "Core 1" compute temp3 @-20,@-20 ``` Now invoking `sensors` shows the adjust values: `$ sensors` ``` coretemp-isa-0000 Adapter: ISA adapter Core 0: +37.0°C (crit = +105.0°C) Core 1: +35.0°C (crit = +105.0°C) ... ``` #### Example 2\. Renaming labels This is a real example on an Asus A7M266\. The user wishes more verbose names for the temperature labels 'temp1' and 'temp2': `$ sensors` ``` as99127f-i2c-0-2d Adapter: SMBus Via Pro adapter at e800 ... temp1: +35.0°C (high = +0.0°C, hyst = -128.0°C) temp2: +47.5°C (high = +100.0°C, hyst = +75.0°C) ... ``` Create the following file to override the default values: `/etc/sensors.d/Asus_A7M266` ``` chip "as99127f-*" label temp1 "Mobo Temp" label temp2 "CPU0 Temp" ``` Now invoking `sensors` shows the adjust values: `$ sensors` ``` as99127f-i2c-0-2d Adapter: SMBus Via Pro adapter at e800 ... Mobo Temp: +35.0°C (high = +0.0°C, hyst = -128.0°C) CPU0 Temp: +47.5°C (high = +100.0°C, hyst = +75.0°C) ... ``` #### Example 3\. Renumbering cores for multi-CPU systems This is a real example on an HP Z600 workstation with dual Xeons. The actual numbering of physical cores is incorrect: numbered 0, 1, 9, 10 which is repeated into the second CPU. Most users expect the core temperatures to report out in sequential order, i.e. 0,1,2,3,4,5,6,7. `$ sensors` ``` coretemp-isa-0000 Adapter: ISA adapter Core 0: +65.0°C (high = +85.0°C, crit = +95.0°C) Core 1: +65.0°C (high = +85.0°C, crit = +95.0°C) Core 9: +66.0°C (high = +85.0°C, crit = +95.0°C) Core 10: +66.0°C (high = +85.0°C, crit = +95.0°C) coretemp-isa-0004 Adapter: ISA adapter Core 0: +54.0°C (high = +85.0°C, crit = +95.0°C) Core 1: +56.0°C (high = +85.0°C, crit = +95.0°C) Core 9: +60.0°C (high = +85.0°C, crit = +95.0°C) Core 10: +61.0°C (high = +85.0°C, crit = +95.0°C) ... ``` Again, run `sensors` with the `-u` switch to see what options are available for each physical chip: `$ sensors -u coretemp-isa-0000` ``` coretemp-isa-0000 Adapter: ISA adapter Core 0: temp2_input: 61.000 temp2_max: 85.000 temp2_crit: 95.000 temp2_crit_alarm: 0.000 Core 1: temp3_input: 61.000 temp3_max: 85.000 temp3_crit: 95.000 temp3_crit_alarm: 0.000 Core 9: temp11_input: 62.000 temp11_max: 85.000 temp11_crit: 95.000 Core 10: temp12_input: 63.000 temp12_max: 85.000 temp12_crit: 95.000 ``` `$ sensors -u coretemp-isa-0004` ``` coretemp-isa-0004 Adapter: ISA adapter Core 0: temp2_input: 53.000 temp2_max: 85.000 temp2_crit: 95.000 temp2_crit_alarm: 0.000 Core 1: temp3_input: 54.000 temp3_max: 85.000 temp3_crit: 95.000 temp3_crit_alarm: 0.000 Core 9: temp11_input: 59.000 temp11_max: 85.000 temp11_crit: 95.000 Core 10: temp12_input: 59.000 temp12_max: 85.000 temp12_crit: 95.000 ... ``` Create the following file overriding the default values: `/etc/sensors.d/HP_Z600` ``` chip "coretemp-isa-0000" label temp2 "Core 0" label temp3 "Core 1" label temp11 "Core 2" label temp12 "Core 3" chip "coretemp-isa-0004" label temp2 "Core 4" label temp3 "Core 5" label temp11 "Core 6" label temp12 "Core 7" ``` Now invoking `sensors` shows the adjust values: `$ sensors` ``` coretemp-isa-0000 Adapter: ISA adapter Core0: +64.0°C (high = +85.0°C, crit = +95.0°C) Core1: +63.0°C (high = +85.0°C, crit = +95.0°C) Core2: +65.0°C (high = +85.0°C, crit = +95.0°C) Core3: +66.0°C (high = +85.0°C, crit = +95.0°C) coretemp-isa-0004 Adapter: ISA adapter Core4: +53.0°C (high = +85.0°C, crit = +95.0°C) Core5: +54.0°C (high = +85.0°C, crit = +95.0°C) Core6: +59.0°C (high = +85.0°C, crit = +95.0°C) Core7: +60.0°C (high = +85.0°C, crit = +95.0°C) ... ``` ### Automatic lm_sensors deployment Users wishing to deploy lm_sensors on multiple machines can use the following to accept the defaults to all questions: ``` # sensors-detect --auto ``` ## Troubleshooting ### K10Temp module Some K10 processors have issues with their temperature sensor. From the kernel documentation (`linux-/Documentation/hwmon/k10temp`): *All these processors have a sensor, but on those for Socket F or AM2+, the sensor may return inconsistent values (erratum 319). The driver will refuse to load on these revisions unless users specify the `force=1` module parameter.* *Due to technical reasons, the driver can detect only the mainboard's socket type, not the processor's actual capabilities. Therefore, users of an AM3 processor on an AM2+ mainboard, can safely use the `force=1` parameter.* On affected machines the module will report "unreliable CPU thermal sensor; monitoring disabled". Users which to force it can: ``` # rmmod k10temp # modprobe k10temp force=1 ``` Confirm that the sensor is in fact valid and reliable. If it is, can edit `/etc/modprobe.d/k10temp.conf` and add: ``` options k10temp force=1 ``` This will allow the module to load at boot. ### Asus Z97/Z190 motherboards With some recent Asus motherboards, fan and voltage sensor access may require the NCT6775 module: ``` # modprobe nct6775 ``` and add to the kernel boot parameters: ``` acpi_enforce_resources=lax ``` ### Gigabyte GA-J1900N-D3V The motherboard use the ITE IT8620E chip (useful also to read voltages, mainboard temp, fan speed). As of October 2014, lm_sensors has no driver support for chip ITE IT8620E [[1]](https://hwmon.wiki.kernel.org/device_support_status_g_i) [[2]](http://comments.gmane.org/gmane.linux.drivers.sensors/35168). lm_sensors developers had a report that the chip is somewhat compatible with the IT8728F for the hardware monitoring part. However, as of August 2016, [[3]](https://www.kernel.org/doc/Documentation/hwmon/it87) lists the IT8620E as supported. You can load the module at runtime with modprobe: ``` $ modprobe it87 force_id=0x8728 ``` Or you can [load the modules](/index.php/Kernel_modules "Kernel modules") during boot process by creating the following two files: `/etc/modules-load.d/it87.conf` `it87` `/etc/modprobe.d/it87.conf` `options it87 force_id=0x8603` Once the module is loaded you can use the *sensors* tool to probe the chip. Now you can also use [fancontrol](/index.php/Fancontrol "Fancontrol") to control the speedsteps of your case fan. ### Laptop screen issues after running sensors-detect This is caused by lm-sensors messing with the Vcom values of the screen while probing for sensors. It has been discussed and solved at the forums already: [https://bbs.archlinux.org/viewtopic.php?id=193048](https://bbs.archlinux.org/viewtopic.php?id=193048) However, make sure to read through the thread carefully before running any of the suggested commands.