You probably have to run BIOS setup (reboot and press F2). Look for the SATA controller option  (maybe it's called "Drive Controller" options) and change it to RAID Autodetect/ATA. I don't see BIOS screens in the online manual, so I can't give you the exact wording of the option. Save the change and exit setup. When you boot from the XP CD and start the Windows installation, you should be offered an option to reformat the hard drive. If you boot from the hard drive, you'll probably end up with both Win7 and XP on the drive, which isn't what you want. You'll also need to install all the right XP-compatible drivers for your hardware after installing XP, starting with System Software (System Utilities), followed by the chipset driver(s), then video, audio, network, etc...  If your XP CD is only SP2, after you install the drivers, you'll have to download SP3 from Microsoft (free) and install it, plus all the recent updates. Otherwise your system will be wide open to all kinds of malware. :emotion-5:  Ron
 Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4  I have studio 1555 with company installed windows 7 Home Premium 64 bit.Now i want to uninstall win 7 and install fresh Win XP Pro (no need any other OS including win 7). When I try to install XP Pro with the bootable cd(32 bit) first it loads installation  files but on starting installation it shows BLUE SCREEN ERROR ask me to restart the system and do scan disk. The Error is:"A problem has been detected and windows has been shut down to prevent damage to your computer..... Technical Details of error:0x0000007B(0xF78D2524,0XC0000034,0X00000000,0X00000000) My system Detail: Dell Studio 1555,core 2 duo T6600,320 Gb SATA HD,3 GB RAM Kindly help me...  
Uninstall company installed windows 7 from dell in dell studio 1555 and 
installing fresh XP Pro SP2.