Process Monitor is an advanced monitoring tool for Windows that shows real-time file system, Registry and process/thread activity. It combines the features of two legacy Sysinternals utilities, Filemon and Regmon, and adds an extensive list of enhancements including rich and...
System Explorer is an enhanced Taskmanager that provides detailed information about running processes, startup programs, IE add-ons (BHOs), drivers, services network connections, system resources and more.Discontinued
While mostly functional it and its website hasn't been updated since 2017 and forums and support are gone.
Resource Monitor is a system application in Microsoft Windows operating systems. It is used to view information about the use of hardware (CPU, memory, disk, and network) and software (file handles and modules) resources in real time.
Performance Monitor is a small program that shows you the CPU, Memory, Disk and Network utilization under Windows NT platforms (2000, XP, Vista, Win 7, etc...).
This program will tell you which programs are accessing your hard disk or using your CPU at any given moment. You will be able to determine why your hard drive is in use or what program is sucking up processor time.