A colorimeter plus free software: test patterns go up, the meter reads what the panel actually shows, and greyscale tracking, primary accuracy and shadow detail become charts with a number on them.

Every disk carries its own health report and hides it in raw numbers. GSmartControl lists the attributes in plain language, highlights the dangerous ones, runs short and long self tests, and keeps the reports for comparison.

Blender Benchmark is the Blender Foundation open source render benchmark, measuring Cycles performance on fixed scenes for CPU and GPU, with scores that can be uploaded anonymously to Open Data and compared with machines worldwide.

UEFITool opens a firmware image layer by layer into volumes, modules and drivers, can extract or replace a module, and runs on all three desktop systems.

Flashrom identifies and reads or writes the flash chip on a board, either through the internal interface or with an external programmer, and asks for a backup first.

A free, open-source fan controller for Windows. It finds the temperature sensors and PWM headers by itself, then lets you draw the relationship between heat and speed, keep several profiles for different scenes and pin the readings to the desktop. Graphics card fans and all-in-one liquid coolers are covered too.

An open-source sidebar for Windows that keeps processor, memory, graphics, network and disk readings on screen permanently, with history charts, threshold alerts, hotkeys and scaling that follows each monitor.

CrystalDiskMark 9.0.3 is a free open source disk benchmark that reports sequential and random throughput in three profiles, reaches back to Windows XP, and ships under the MIT licence.

CrystalDiskInfo 9.9.2 is a free open source drive health monitor that reads S.M.A.R.T. data and reduces it to four states, good, caution, bad and unknown, with USB, RAID and NVMe support.

Libre Hardware Monitor is a free open source hardware monitor for Windows under the MPL, reading temperature sensors, fan speeds, voltages, load and clock speeds, and shipping both a desktop program and a C# library.

GParted 1.8.1 is the stable release listed on the project page, with the live boot image numbered 1.8.1-6. Published as free software under the GNU GPL version 2 or later, it resizes, copies and moves partitions without losing data.