That would be Fedora Core 1, right? Naming is "Fedora Core" for numbers 1...6, and just "Fedora" from 7 on..
First visit should be made to the powersaving control application; Fedora/RedHat have always had those nice graphical tools to change system configuration, so check out what they have for you in the administrative/system menu. On KDE desktop environment you should see the KDE's Control Center, on Gnome the apps are nowadays either separately in the menu, or accessible trough the "Control Panel" -like app, which contains launchers for the various configuration utilities.
Another way is possibly to turn off acpi. That also means turning off the other power management things, such as turning off the machine automatically on shutdown, and so on. You can try it by rebooting and giving the kernel a --noacpi (or was it --acpi=no or --acpi=off, I never remember) option.