The Reliability and Performance Monitor window provides real-time data on your PC’s overall system resource usage, as well as detailed information on the resources that each process is using. It is divided into 5 sections: the resource overview, CPU, disc, network, and memory sections.
The Resource Overview pane will display four scrolling graphs that graphically depict the real-time usage of CPU, Disk, Network, and Memory on your computer. You can use this display to visually analyze current real-time resource usage by each of these components. Clicking on one of the graphs will expand its corresponding details.

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