The Importance of UEFI Settings and Hardware C-States

To manage system behavior, an administrator requires an understanding of selectable UEFI and operating system settings. Many customers use default settings, yet the settings can be modified to optimize system operation. Implementing alternate settings must be done with care.

In this paper we briefly describe the functions that manage system behavior and how they interact with the system hardware. This paper is suitable for users and support personnel that have a basic understanding of system hardware architecture.

Introduction
Managing system behavior and latency
What is affected by behavioral management
Use of the C-states setting
Misuse of the C-states setting
Suggested UEFI settings for operating systems
References
Change history

Changes in the August 13 update:

• Minor corrections

Related product families

Product families related to this document are the following:

• 2-Socket Rack Servers
• 4-Socket Rack Servers
• 8-Socket Rack Servers
• Processors