Step1: Create Bootable USB Drive: Start PowerISO (v4.8 or newer version, download here ). Insert the USB drive you intend to boot from. Choose the menu "Tools > Create Bootable USB Drive". The " Create Bootable USB Drive " dialog will popup. If you are using Windows Vista or Windows 7 / 8 operating system, you need confirm the UAC dialog to continue. In "Create Bootable USB Drive" dialog, click "..." button to open the iso file of Windows 7 or Windows 8. Select the correct USB drive from the "Destination USB Drive" list if multiple USB drives are connected to the computer. Choose the proper writing method. "USB-HDD" is recommended. Click "Start" button to start creating windows 7 / 8 bootable USB drive . If no errors occurred in the above process, you should now be all set to setup Windows 7 / 8 from USB drive ! Step 2: Configuring the BIOS: You should now reboot and go into the BIOS configuration to boot from ...