Sony PCG-SRX99K - Manual (Page 199)

Use the PowerPanel utility to change the Thermal Control Strategy setting to Quiet. This setting slows down the CPU
speed. See PowerPanel Help for more information.
To reduce fan noise
1. Right-click the Battery icon on the taskbar, and select Edit/Create Profiles. The Profile Editor window appears.
2. Double-click System to open the file if it isn't already opened.
3. Double-click Thermal Control Strategy - Performance, and select Quiet.
4. Restart your computer.
Why does the System Properties dialog box display a slower CPU speed than advertised?
This is normal. Because your computer's CPU utilizes a type of CPU speed controlling technology for power conservation
purposes, System Properties may display the CPU's current speed instead of the maximum speed.
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