Windows Performance Tools Kit

A tool to measure CPU load during the boot process. Below is from the product homepage.

The Windows Performance Tools (WPT) Kit contains performance analysis tools that are new to the Windows SDK for Windows Server 2008 and .NET Framework 3.5. The WPT Kit is useful to a broad audience, including system builders, hardware manufacturers, driver developers, and general application developers. These tools are designed for measuring and analyzing system and application performance on Windows Vista, Windows Server 2008, and later.