Hi,
You can run System Monitor (perfmon.exe) to gain some device usage information by add some counters. You need analyze the information apply to your scenario.
Diskspace, add %Free Space counters for each logical Disk.
Bandwidth, you can add counters such as Total Bytes Received/Sent, Total Get/Post Request, Total blocked bandwidth bytes and etc, these counters depend on different web services(The web services’ instances are your web site) .
CPU and memory usage, you can add %Idle Time and %Processor Time counters for your Processor. Add %Committed Bytes In Used and Available Mbytes counters for you Memory. If your IIS runs in worker process isolation mode, you can add %Processor Time and Page File Bytes counters for each w3wp.exe.
Additionally, you can monitor system online. You also can create a new performance log setting and adjust the start/stop time in the schedule tab, this will allow you collect information by different forms.