OBS Studio - Free and open source software for video recording and live streaming for Mac, Windows and Linux.
Open Hardware Monitor - Monitors temperature sensors, fan speeds, voltages, load and clock speeds, with optional graph.
MWSnap - MWSnap is basically a free to use Windows snapping tools that are used for snapping any part of the screen that is currently displaying on the front of all opened programs and windows.
Guru3D - Guru of 3D: PC Hardware Reviews and tests
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
Geforce Experience - GeForce Experience is a new application from NVIDIA that optimizes your PC in two key ways.