Windows has a feature which can be set from the Power Options menu where the CPU is automatically throttled according to usage in order to save power.
How can I view this throttling in real time? For instance, is the CPU Usage in Windows Task Manager a good indicator?
Windows 7 has a tool called Resource Monitor which shows this. You can launch it by pressing Windows+R to bring up the Run dialog, then type perfmon.exe /res and press Enter.
On the CPU panel, the Maximum Frequency (small blue graph) shows at what power the CPU is currently operating.
I like using CoreTemp. It runs as admin, but it's free and signed by GlobalSign in the authors name.
What's cool is seeing how throttling conserves energy. Here's an example:
