This document explains the modified method of replacing the low-version operating system with the preinstalled WINDOWS8 model, since the ThinkPad computer randomly does not have a Windows 8 recovery disc, if you still want to retain the preinstalled genuine Windows 8 system, create a recovery media advance reservation before replacing the system, as described in the Create recovery media method
Warm tip: Dear Lenovo users, in order to prevent accidental loss of computer data risk, we recommend that you regularly back up your important data to third-party storage media (such as servers, CD-ROM, mobile storage devices, etc.) to ensure your data security.
Operation Method:
1. During the boot process, click F1 to enter the BIOS interface;
2. Enter Security---Secure boot to modify the secure boot to Disabled;
3. After continuing to enter the startup-uefi/legacy boot option under BIOS, here are two options:
1) uefi/legacy boot option is selected as Both,uefi/legacy boot priority selected as UEFI first. This method applies to all versions of the operating system installation;
If the installation process produces the error "device driver not found" as shown in the second picture. Generally because the GPT partition is not recognized, the installation of the method can solve the problem;
2) uefi/legacy boot selected as UEFI ONLY,CSM Select Yes. Can be understood as a UEFI compatibility mode. This method is only available for Windows 7 SP1 versions that can support UEFI installation using CD-ROM;
4. If you need to install XP or an earlier operating system, you need to modify the AHCI in Config-serial ATA (SATA)-SATA Controller Mode option to compatibility, (Vista, Win7 and other high-version systems without changes);
5. After inserting the operation installation disc, click F10 (or FN+F10) to select Yes, save the BIOS settings and exit;
6. The machine will restart automatically, then power on click F12 (or FN+F12) Select Disc boot, follow the installation instructions for Windows 7 to continue to install the operating system.
