iStat
Commercial
iStat is an advanced Mac system monitor for your menubar.
Real Temp
Free
Real Temp is a temperature monitoring program designed for all Intel processors.
Core Temp
Free
Core Temp is a compact, no fuss, small footprint, yet powerful program to monitor processor temperature and other vital information.
Sidebar Diagnostics
Open Source
SidebarDiagnostics is a simple sidebar for Windows desktop that displays hardware diagnostic information.
Compare SpeedFan with alternatives
Compare Sidebar Diagnostics and SpeedFan and decide which is most suitable for you.