USB devices store standard descriptors in firmware for the device, and its interfaces and endpoints. Independent Hardware Vendors (IHVs) can also store class and vendor-specific descriptors. However, the types of information that these descriptors can contain is limited.
So Microsoft implemented OS Descriptors, to enlarge potentialities of IHVs. These descriptors can be used by IHVs to store in firmware much of the information that is now typically provided to customers separately.
Here you can download OS Descriptors.
Measuring Windows Vista Performances
This paper provides information about measuring performance on Windows Vista. It provides guidelines for technical users and professionals who are creating benchmark tests to create accurate, repeatable workloads and measurements.
This paper explains how to evaluate system energy efficiency and demonstrates example power policy settings to favor power savings or performance. Best practices for energy-efficient platform design are also covered.
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