Free, portable system utility Auslogics Task Manager helps you troubleshoot a PC by tracking CPU, disk, memory, and internet usage for every process on your system.
Auslogics Task Manager is very similar to Process Explorer, arguably the best of the bunch. Where Auslogics Task Manager shines, however, is that it's extremely simple and easy to figure out which processes are utilizing the hard drive or network connection—you can even select a specific process and see just how much a specific process is hitting the disk. Like many other utilities, you can also search for an unknown process to figure out what it is, or you can see a list of open files to see what is locking a particular file.
Auslogics Task Manager is a free download for Windows only. Readers should note that the regular setup tries to force the awful Ask Toolbar onto your computer, so you'll want to grab the crapware-free portable version instead.