athcool - control power-saving mode on AMD Athlon/Duron CPUs -------------------------------------------- 1. Introduction -------------------------------------------- athcool is a program that controls the power-saving mode on AMD Athlon/Duron CPUs. Since enabling power-saving mode, you can save power consumption, lower CPU temprature when CPU is idle. athcool only sets/unsets the "Disconnect enable when STPGNT detected" bit in the northbridge of the chipset. To save power, someone has to send the STPGNT signal when the CPU is idle. This is done by the ACPI subsystem when the C2 state is entered. Hence, you need ACPI support in your kernel to achieve power savings. !!!WARNING!!! Depending on your motherboard and/or hardware components, enabling Athlon powersaving mode may cause: * noisy or distorted sound playback * a slowdown in harddisk performance * system locks or instability * massive corruption of the filesystem (rare, but observed at least once) Before use athcool, you must recognize these potential DANGERS. Please use athcool AT YOUR OWN RISK. athcool is supplied "as is". The author disclaims all warranties, expressed or implied. The author and any other persons assume no liability for damages, direct or consequential, which may result from the use of athcool. Osamu Kayasono <jacobi@jcom.home.ne.jp> http://members.jcom.home.ne.jp/jacobi/linux/softwares.html -------------------------------------------- 2. Supported Chipsets -------------------------------------------- VIA KX133 VIA KT133/KM133/KL133/KN133[A] VIA KT266/333[A] VIA KM266 VIA P/KN266 VIA KT400[A]/KM400/KT600 SiS 730/733 SiS 735/740/741/745/755 SiS 746[FX]/748 nVIDIA nForce nVIDIA nForce2 AMD AMD-751/761 (AMD AMD-762) * AMD-762 Chipset has not support HALT disconnect, so Powersaving only enables when S1 or S3 state entered see http://members.jcom.home.ne.jp/jacobi/linux/softwares.html for more information -------------------------------------------- 3. Installation -------------------------------------------- make (become root if necessary) make install Good luck! * required libraries and header files of pciutils, when building athcool. -------------------------------------------- 4. Usage -------------------------------------------- /usr/sbin/athcool [options] supported option: on Enable power-saving mode off Disable power-saving mode stat Quely power-saving mode list List supported chipsets * install and use athcool, you need super user privilege. -------------------------------------------- 5. Related and Useful links -------------------------------------------- * CoolOn Project http://coolon.o-ya.net/ * pciutils http://atrey.karlin.mff.cuni.cz/~mj/pciutils.shtml * Athlon Powersaving HOWTO http://www.daniel.nofftz.net/linux/Athlon-Powersaving-HOWTO.html * LVCool http://vcool.occludo.net/