Orion from GameSonic has released an updated version of System Manager Plugin, a homebrew app that allows you to control the fan speed of your PS3, here is a quote from the thread:
Changelog:Compatible with all existing cobra CFW(Except 4:53 dex Rebug).
Much improved fan Control.
The led alternates depending on the temperature as the homebrew system manager.
Installation:Place the files for your CFW,that you find in the store,in the hdd0.
Place the boot_plugins file,that you found in the store,in hdd0
You can tell the temperature of the led console:
Yellow Led fixed: temperature below 70 degrees
Amber/green LED flashing temperature above or equal to 70 degrees
LED red/yellow/green blinking temperature above or equal to 75 degrees
Estwald/Miaralatijera: Original Developers
Rancid: First dev have made the port a plugin for CfW 4.50 DEX.
Orion: developer improved version for all CFW COBRA CEX.
Discuss the hombrew at PlayStationHaX forum, by clicking here.