If your Gateway notebook has Windows 8 included, you can use the built in Reset feature to reset your system to factory defaults. Instructions on how to perform this task can be found here from Microsoft Support
. If the system is properly configured with a recovery image which is aware of the Reset feature, the factory image will be as the system arrived from Gateway. If it is not properly configured, Windows 8 will be reset as though it had been installed fresh from disk and may require installation of drivers from Gateway to function fully.