1) make a backup of the folder / System / Library / Extensions /
2) downloaded from Apple update
Leopard 10.5.1 - 10.5.2 - 10.5.3 - 10.5.4 - 10.5.5 - 10.5.6 - 10.5.7
I would advise you to gradually update the next release.
Do not skip any Relase !!!!!!!!!!!!!!!!!!
WARNING! DO NOT USE Software Updater!
3) Open the Terminal (Applications - Utilities)
4) type: sudo-s
5) Start the installer and just open the "Installer"
and enter your password to get the necessary permissions.
(NB: E 'MUST HAVE Set a password, if you did not, do it before you perform these instructions!).
6) copy the string of instructions below:
while sleep 1 do rm-rf / System / Library / Extensions / AppleIntelCPUPowerManagement.kext; done
and press Enter.
7) DO NOT CLOSE THE TERMINAL.
Start the 10.5.7 update to finish and leave
8) After installation RESTART NOT !!!!!!!!!!
Move the dialog and return in the terminal.
9) Press CTRL + C to terminate the process carried out in section 5.
10) Cross your fingers and then restart your MAC ... ... ...
Repair permissions and have fun