Alternatives to GNOME System Monitor

Facter suits system administrators and Puppet users who need to gather and use machine facts in manifests or reporting workflows.

Fastfetch

Fastfetch suits command-line users who want system details in a terminal, whether for diagnostics, startup greetings, or desktop screenshots.

Btrfsmaintenance suits Linux administrators maintaining Btrfs filesystems who want scheduled maintenance scripts.

AIDA64 Extreme suits home users who want detailed PC information and monitoring.

It suits Linux and BSD developers debugging hardware issues and organisations simplifying hardware inventory.

ASTRA32 suits PC repair technicians and system administrators who need component details, driver checks, or machine reports.

EtreCheckPro

The free mode suits Mac users who want diagnostics, a shareable report, or command-line use.

Autoruns

Autoruns suits Windows users who want to inspect and manage configured startup entries, including entries for other accounts.

AppControl

AppControl suits Windows users investigating background activity, including gamers, IT professionals, privacy-conscious users, and people troubleshooting applications.

SIW suits administrators and technicians who need detailed Windows system information or exportable reports.

htop

htop suits users who need terminal-based process monitoring on Linux or macOS and related Unix systems.

Speccy

Speccy suits home users who want to inspect PC components, temperatures, or diagnostic data and save system reports.

It suits Linux users who want system details through command-line options or IRC.

It suits Windows users who want a tray indicator for packet activity on available interfaces.