SpeedFan!

iStat is a series of system monitor apps. It's available in different versions: iStat Menus, iStat for iOS and iStat Server as a companion application to the iStat for iOS app that lets you remotely monitor your computers (free for Windows and Mac).

Core Temp is a compact, no fuss, small footprint program to monitor CPU temperature.

SidebarDiagnostics - A simple sidebar for Windows desktop that displays hardware diagnostic information.

smcFanControl is the perfect application for all those Macbook owners getting burned by their hot-running Macbook.This Mac application allows you to control the speed of the fan in your MacBook so you can avoid it running hot.

Real Temp is a temperature monitoring program designed for all Intel single Core, Dual Core, Quad Core and Core i7 processors. Each core on these processors has a digital thermal sensor (DTS) that reports temperature data relative to TJMax which is the safe maximum operating core temperature for the CPU. As your CPU heats up, your Distance to TJMax will decrease. If it reaches zero, your processor will start to thermal throttle or slow down so maximizing your distance away from TJMax will help your computer run at full speed and more reliably too. »

cinnamon-cpufreq-applet - Port of Gnome 3 CPUFreq applet to Cinnamon - with some fixes.

TPFanControl will reduce the fan noise of your IBM/Lenovo Thinkpad.

iMac users who tweak their systems using 3rd party hard disks or solid state disks, are often surprised by an unpleasant aftermath: an annoyingly noisy hard disk fan. Fan management in Apple systems relies on temperatures reported by the SMC system. The SMC collects data from external sensors or by reading the internal hard disk temperature in a proprietary manner. Sometimes reusing the external sensor is not possible or, as in more recent generations of iMacs, replacing the original hard disk breaks the system’s temperature monitoring. In both cases the SMC system tends to go into frenzy and drive you mad with a loud fan. »

Using a database, it will show information about your SSD, such as the controller, processing tech, NAND type etc.Other useful information related to disk devices are also shown, such as S.M.A.R.T. status and partition layout.

Lm-Sensors is a free and open-source application that provides tools and drivers for monitoring temperatures, voltage, and fans.

Monitoring temperatures and status of system components such as CPU, GPU and hard disk drive, fan speeds

Personalize your experience with state-of-the-art real-time overclocking*. Used by world record setting overclockers across the globe, AMD OverDrive™ gives you unprecedented control over your processor, memory and chipset to push the performance envelope further than ever before.

fancontrol is a shell script for use with lm_sensors. It reads its configuration from a file, then calculates fan speeds from temperatures and sets the corresponding PWM outputs to the computed values.