1. Insert the Windows 7 DVD or have a dump of Windows 7 Installation files ready in your HDD or somewhere in the netwrok.
2. . Just plug in a USB stick with enough space to store Windows Installation files.
3. Download Diskpart utility from here.
4. Run Diskpart.exe as administrator.
5. Execute the following commands:
6. Now just Copy the windows installation files from the DVD to the USB stick, boot from USB stick and happy installaton!!