Win7 Ultimate To WinXP SP3

Hello!

I have a question about installing WinXP SP3, my current OS is Win7 Ultimate and I want to change it to WinXP SP3, my question is: Do I need to install WinXP SP1 and WinXP SP2 in order to install WinXP SP3 or it's ok to install WinXP SP3 directly without installing the SP1 and SP2?

I downloaded the WinXP SP3 here: Download: Windows XP Service Pack 3 - ISO-9660 CD Image File - Microsoft Download Center - Download Details

I don't know if that is Full Installer or a Update only....

No, you don't need to install SP1 and SP2 first. Just burn the downloaded ISO image to a disc. From the download link you provided:

Windows XP Service Pack 3 (SP3) includes all previously released updates for the operating system.

Just a suggestion. Since you're using Ultimate, why not install XP Mode? It runs inside Windows 7 as a virtual machine. If you uninstall Windows 7 and replace it with XP, you may have problems finding the correct drivers drivers, etc. Not to mention long-term support which ends April 2014.

Windows XP Mode - Install and Setup

0k thanks, I'd like to use/install that WinXP Mode but the reason why I'd like to change my OS is that Win7 takes a lot of memory, my CPU Usage sometimes become 100% when I played or run a single/multiple applications...

My Computer Specs:
OS: Win7 Ultimate SP1
Processor: AMD Sempron(tm) 140 Processor 2.70 GHz
RAM: 3gb

another question, My OS is still Win7 Ultimate, and I have a winxp cd n0w, if i install winxp without deleting the current partitions and install WinXp in Local Disk C did all my files in Local Disk D will be deleted also?

No, they won`t.

If you can find an XP with SP3 installer for your licensed version (and in the OEM sku if your PC came with XP) then you'll save hours of updating from installing with XP with no SP or SP1.

May I ask why you are replacing Win7 with XPired? Did it come on the machine? You can virtualize XP from within the modern Win7 OS much easier if you just have a few programs that are too old like XP.