Below are the steps for resolving the issue with the computer which is not booting correctly after SP3 is installed in the computer.
1) Start your computer in Safe Mode.
2) Click on Start, Run, and type REGEDIT and press the Enter key. This will open the Registry Editor on the desktop.
3) Click the plus (+) next to the following registry keys to move it to the accurate spot.
HKEY_LOCAL_MACHINE
SYSTEM
Current Control Set
Services
Intelppm
4) In the right hand column find the entry of titled START and double-click on it.
5) Alter the number to 6 and then click at Ok
6) Close the Registry Editor
7) Shut down your computer and restart it again.

This time the computer will restart generally and finish the installation of SP3.