If you’re fond of keeping tabs on what your computer is doing, then the set of UsefulGadgets are what you’re looking for. Monitor CPU activity, disk activity, and disk space. Each gadget is installed separately so you can pick and choose which you want to use.
NOTICE: Are your gadgets showing incorrectly or not showing up at all? Microsoft provides a fix for this on their article Windows 7 gadgets may not work or be displayed correctly. Scroll down to Method 4 and download the Fix It installer.
