After making several reinstalls on various laptops for work all needing SP3 installed I remembered the /nobackup flag for starting the install. so in in the command line you drag and drop the sp3 installer and then type /passive /nobackup /forcerestart and then walk away for a bit (but less time then if you had to backup the data) Yes it may be more risky, but since it is a clean install why bother with worrying about that!
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Service Pack 3 Setup
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AVAILABLE SWITCHES:
[/help] [/quiet] [/passive] [/norestart] [/forcerestart] [/warnrestart] [/promptrestart] [/overwriteoem] [/nobackup] [/forceappsclose] [/integrate:] [/d:] [/log:]
/help Displays this message
SETUP MODES
/quiet Quiet mode (no user interaction or display)
/passive Unattended mode (progress bar only)
RESTART OPTIONS
/norestart Do not restart when installation is complete
/forcerestart Restart after installation
/warnrestart[:] Warn and restart automatically if required (default timeout 30 seconds)
/promptrestart Prompt if restart is required
SPECIAL OPTIONS
/overwriteoem Overwrite OEM files without prompting
/nobackup Do not backup files needed for uninstall
/forceappsclose Force other programs to close when the computer shuts down
/integrate: Integrate this software update into
/d: Back up files into
/log: Create log file at
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