This tutorial shows how to install Window 7 instead of Windows 8 on Sony VAIO. The process might also be called downgrading.
- Go to BIOS, by pressing Assist button instead of power button when your computer is shut down.
- Disable safe boot and set boot mode to Legacy instead of UEFI.
- Now Windows 7 cd should boot.
- Proceed with the installation until you see the partitions. In custom mode you have to delete all partitions before you can install.