Popular CPU/GPU/Power Supply testing tool.
OCCT is the most popular CPU/GPU/Power Supply testing tool available. Free to use for the end user, it has 13M downloads since its creation in 2003. It monitors your computer while the test is in progress, and protects your components by stopping automatically once a component reaches a critical temperature.
OCCT has 4 different tests : CPU:OCCT, the historical test, very accurate, CPU:Linpack, the popular error detection tool, GPU:3D, a custom 3d test, and Power supply, that combines CPU:Linpack and GPU:3D to load your power supply. It will monitor your computer and present you real-time graphs showing you temperatures, voltages, fan speed, frequencies, component usage, and power comsumption during your tests.
Should a component reach a critical temperature during a test (by default, 85°C), OCCT will stop itself immediatly. At the end of a test, you will be able to save a full graphical report of what happened during the test, for diagnostic purposes