HWMonitor
Open Hardware Monitor
Core Temp
AIDA64
HWiNFO
SpeedFan
CPU-Z
Speccy
eul
Stats
iStat Menus
RunCat
Stats Panel
SpeedFan
Open Hardware Monitor
MenuMeters for El Capitan
eulHWMonitor is recommended for users who wish to monitor their computer's hardware performance. This includes PC enthusiasts, gamers, overclockers, and IT professionals who need to ensure their systems run smoothly and diagnose potential hardware issues. It's also suitable for casual users who want to keep an eye on system stability.
Open Hardware Monitor - Monitors temperature sensors, fan speeds, voltages, load and clock speeds, with optional graph.
Stats - Simple macOS system monitor in your menu bar.
Core Temp - Nov 4, 2017 - Core Temp is a compact, no fuss, small footprint, yet powerful program to monitor processor temperature and other vital information.
iStat Menus - "An advanced Mac system monitor for your menubar."
AIDA64 - AIDA64 is a system information, diagnostics and benchmarking solution for Windows PC.
RunCat - This cat runs at the speed according to the CPU usage of your Mac. By looking at its running, you can see how much your CPU load is.