HWiNFO - Professional System Information and Diagnostics. Comprehensive Hardware Analysis, Monitoring and Reporting for Windows and DOS. FREEWARE. download. Advertisements.
MSI Afterburner - Tool to manage video cards. Shows video card stats (temp, GPU usage, etc.).
Neofetch - Fancier version of Screenfetch that displays colors and supports more platforms.
ASUS GPU Tweak - ASUS GPU Tweak fully implements TechPowerUp’s GPU-Z analysis and monitoring features.
Speccy - Speccy - find the details of your computer's specs. Great for spotting issues or finding compatible upgrades. Download the latest version free.
Guru3D - Guru of 3D: PC Hardware Reviews and tests