Venmon is a system resource monitoring and multi-ping tool for Windows. It can monitor system memory, processor, battery life, uptime, idle time, network traffic, and drives. It uses minimal processing power and memory usage while displaying real-time statistics. Venmon can run in portable mode, such as off a USB stick and does not require the installation of runtime modules such as .Net, Java, C++. Freeware with no bundled malware or advertisements.
NetSpeedMonitor - NetSpeedMonitor is a lightweight Network Monitoring Toolbar for your Windows Taskbar
TinyResMeter - TinyResMeter is a small tool that displays useful information about system resources in real time...
FreeMeter - Monitor network bandwidth (C#.NET 2k/XP+). Desktop and Systray graph.
Taskbar Meters - Incredibly simple meters that live in the Windows 7 task bar.
NetTraffic - Essential network bandwidth monitor.
MenuBar Statistics - MenuBar Statistics is a lightweight app that sits quietly in your menu bar of macOS and displays computer information such as CPU, Disk, and Network, which is updated every 5 seconds.