How to Enable AMD Cool'n'Quiet Feature in Windows XP

Cool'n'Quiet is a CPU speed throttling and power saving technology introduced by AMD with their Athlon 64 processor line. It works by reducing the processor's clock rate and voltage when the processor is idle. The aim of this technology is to reduce overall power consumption and lower heat generation, allowing for slower (thus quieter) cooling fan operation. The objectives of cooler and quieter result in the name Cool'n'Quiet. The technology is similar to Intel's SpeedStep and AMD's own PowerNow!, which were developed with the aim of increasing laptop battery life by reducing power consumption.

Due to their different usage; Cool'n'Quiet refers to desktop and server chips, while PowerNow! is used for mobile chips — the technologies are similar, but not exactly equivalent. This technology was also introduced on "e-stepping" Opterons, however it is called Optimized Power Management, which is essentially a re-tooled Cool'n'Quiet scheme designed to work with registered RAM.

For this, you must have one of these AMD processors below:

Processors supporting Cool'n'Quiet
* Athlon 64 & X2 - all models
* Athlon 64 FX - FX-53 (Socket 939 only) and higher
* Sempron - Socket 754: 3000+ and higher; Socket AM2: 3200+ and higher
* Opteron - E-stepping and higher, branded as Optimized Power Management
* Phenom - all versions support Cool'n'Quiet 2.0
And the most important is you have a mainboard with Bios that support Cool'n'Quiet Feature.

Firstly, you have to download and install latest AMD Processor Driver and AMD Dual-Core Optimizer.
Click this to download AMD Processor Driver Version 1.3.2.0053 for Windows XP
Click this to download AMD Dual-Core Optimizer
The AMD Dual-Core Optimizer can help improve some PC gaming video performance by compensating for those applications that bypass the Windows API for timing by directly using the RDTSC (Read Time Stamp Counter) instruction. It can make the system more faster by patching windows to run in multi-core processors with stable.

To enable the Cool ‘n’ Quiet feature on a Windows XP system, you have to change the power scheme. Open the ‘Power Options’ from the Control Panel. Choose the power scheme ‘Minimal Power Management’ and click ‘OK’ to enable Cool ‘n’ Quiet.

To check Cool ‘n’ Quiet functionality, a third party application that measures the current processor clock speed of the computer, such as WCPUCLK or CPUZ, can be used. Under Windows XP only, a built-in indicator of current processor frequency is included.

Checking for Cool ‘n’ Quiet functionality:
1. With no programs running with Windows at idle, start CPUZ or similar program.
2. If the displayed clock frequency is approximately 800 or 1000 MHz, Cool ‘n’ Quiet is enabled and functioning correctly.

Checking for Cool ‘n’ Quiet functionality (Windows XP only):
1. Click on Start, and open up the Control Panel. Click on Performance and Maintenance, and then click System.
2. Under General, if the displayed clock frequency is approximately 800 MHz, Cool ‘n’ Quiet is enabled and functioning correctly.