I have a machine running Windows XP and the fan is loud until the login screen comes up. It is quiet after that. If I use a PE disk the fan stays loud and never gets quiet. Why does it become quiet with the installed version? Why does it stay loud with the PE? How can I make it quiet all the time?
This appears to a driver problem, since the fan you are referring to is most likely the video card fan. Some video cards have fans that run at full speed until software controls the fan speed; as an example, I have a Linux system with an Nvidia GeForce GT 220 card that is very loud unless the X Window System is running, when the full drivers are loaded. You need to add appropriate video drivers to the PE disc so that there is software to control the video card's fan.