As you know, Windows System Information dialog shows you the hardware resources, installed components, and other configuration related information. It also gives you a chance to run some diagnostics tools and much more… The help file says that to display system data you need to “click Start, and then click Help and Support. Click the Support button on the toolbar, and then, under Tools and Links on the left side of the window, click Advanced System Information. In the details pane, click View detailed system information“.
However, you could simply hit Start -> Run (Windows Key + R), type in msinfo32 and hit Enter to get to the same tool.