1. Introduction

1.1. Basics on the Athlon Power Saving Mode

The HLT signal which is used by the normal idle-loop of the Linux kernel doesn't normaly bring any significant power-saving on processors of the Athlon/Duron family (hereafter referred to as Athlon processors). To get real power-saving on an Athlon processor, you have to put the processor in the STPGNT-Mode (Stop Grant Mode). In this mode, the processor is disconnected from the front-side bus (FSB), and can turn off parts of the CPU as well as reduce the clock to save power.

Some modern Motherboards/Chipsets also support a Function to make a STPGNT when a HLT signal is detected.

1.2. Copyright and License

This document, Athlon Powersaving HOWTO, is copyrighted (c) 2003,2004,2005 by Daniel Nofftz.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is available at http://www.gnu.org/copyleft/fdl.html.

Linux is a registered trademark of Linus Torvalds.

1.3. Disclaimer

No liability for the contents of this document can be accepted. Use the concepts, examples and information at your own risk. There may be errors and inaccuracies, that could be damaging to your system. Proceed with caution, and although this is highly unlikely, the author(s) do not take any responsibility.

All copyrights are held by their respective owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark. Naming of particular products or brands should not be seen as endorsements.

1.4. Feedback/Questions/Support

Feedback is most essential for this document. New solutions for new chipsets are especially needed, as are comments, whether the provided solutions work or don't work. Also please report spelling errors if you find them, cause i am no native english speaker. Send your additions, comments, criticisms and questions to the following email address: <daniel@nofftz.net.NOSPAM>. You can email me in German or English!

If you want to support me, you could donate through Paypal (to the same email-adress) or send me some new Hardware to play with. ;)

1.5. New Versions of this Document

The newest version of this HOWTO will always first be made available here.