This is the reply from ASUS:
Thank you for your trust in our support ASUS.
My name is Mike and i will try to offer you the best support for our products.
The Windows 8.1 still has a lot to improve when it comes to hardware/software compatibility, therefore i recommend rolling back to Windows 8, as the product came preinstalled with in the first time. You can follow the bellow procedure in order to restore back: Attention! Please plugin the charger during the process and also be advised that after restoring the operating system, all data will be lost!
1. Completely turn off the PC by holding the Power Button pressed for 30 seconds;
2. Right after you turn on the PC, start pressing the F2 key repeatedly to enter BIOS;
3. In BIOS, on the BOOT section, set the Fast Boot on Disabled;
4. Press the F10 key to save settings and exit BIOS;
5. Start pressing, repeatedly, the F9 key to access the Recovery Menu;
6. Select Troubleshooting and pick one of the Options: - Refresh your PC (brings the PC back to factory settings, without losing data on the other partitions); - Reset your PC (brings the PC back to factory settings with data loss);
7. Follow the on-screen instructions and wait until the recovery process is completed. For any type of questions or issues you encounter with the products (hardware or software), feel free to contact us whenever you need. Don't hesitate to reply to the e-mails you're receiving from us. We hope that our support will be useful and we wish you a great day ahead. Best Regards, Mike ASUS Technical Support, http://za.asus.com/http://support.asus.com/