|All the regular Microsoft XP CDs that have SP1 updates included that I've seen DO NOT have SP1 printed on the CD, but the volume labels - the labels you see for the CD in Windows - for CDs with SP1 updates included are different from those with no SP updates at all - you can search using that volume label to determine whether it has SP1 updates or not.|
If your XP CD DOES already have SP1 updates , if you have installed Windows, System Information will show you have SP1 updates.
(Start - Run - type: msinfo32 (press Enter) - look on the right hand side on the first page you see)
If you don't have any Windows SP updates in your Windows installation, you have to install SP1 or SP2 updates before you can install SP3 updates.
If you're making yourself a "slipstreamed" CD, if you don't have any SP updates on your Windows CD, you can integrate SP3 updates into the "slipstreamed" CD's contents without having to integrate SP1 or SP2 updates into it's contents first.