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System monitors collect information about the hardware resources. System monitors are extremely useful for determining utilization, the measure of the percentage of the resource we are using (i.e. 20% GPU utilization ). System monitors also measure the amount of a given resource we are using ( i.e. 235 megabytes of ram ).
Windows XP provides two system monitors with their operating system. The first, and more general system monitor, exists in the task manager. By clicking on the “performance” tab, you can view information about the stage of the current hardware. The second, is an administrative tool called “Performance”. Here, you can add or remove different resources to monitor.

System monitors are also available for the GPU. Having a system monitor for your GPU is critical to efficient optimization opportunities. Our first step to determining where an optimization opportunity in a video game exists is to determine if the GPU is running near full utilization or not. This is done with a GPU system monitor.