sms2003_150x70 These are the following minimum steps you need to follow:
Pre-install tasks (preflight)
Verify SMS 2003 SP3 requirements (SQL & Windows Server OS versions/SP)

Using the SMS Deployment Readiness Wizard:

Backup SMS SQL Database
Restore SMS SQL Database with new DB name
Run SMS Deployment Readiness Wizard
Review SMSSetup.log
Verify that SMS is running correctly (pre-SP3 install)
Review MPcontrol.log file has no errors
Verify SMS client is reporting correctly
Test client discover
On SMS Server, verify client is reporting
Service Pack 3 install and verify
Backup existing SMS MOF file
Run SP3 install
Reinstate original MOF file
Verify that SMS is running correctly (pre-SP3 install)
Review MPcontrol.log file has no errors
Verify SMS client is reporting correctly
Test client discover
On SMS Server, verify client is reporting
Review SMS log files
Review SMSSetup.log
Review mpsetup.log to ensure completion
Review mpcontrol.log to ensure a) completion and b) http 200 messages being received.
Review SMSSiteComp.log
Review Hman.log (if applicable)
Review Inboxmgr.log
Verify SMS Reporting Point is still working (Central Server only)
Post install hotfixes
Apply Hotfix KB971225 (Windows 2008 & Vista detection)
Apply Hotfix KB941214 (Updated Client.MSI)
Apply Hotfix KB974014 (Windows 7 and Windows Server 2008 R2 support)
Reboot server
SMS Client on Server install
Install client.msi on server
Verify sms client on server
Post SP3 install tasks
Check version in SMS Console / Site heirachy is now SP3
Update OSD Feature pack
Reboot server
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