Can you please post your dxdiag report here? There some more information about the configuration I would like to check.
Thanks for the information.
Based on all information I have received I recommend you doing the following:
1. Update the bios in your system provided by the computer manufacture.
2. Uninstall the driver and download the latest at the following link:
3. Test a different HDMI cable and if possible do not use video adapters.
The screen tearing is still present.
It is important to confirm with the OEM if your computer has any limitation to run Win 8.1. Sometimes manufactures set limitation on their units and this could be one. At this point, since you have done all troubleshooting steps my recommendation is to contact the computer manufacture so they can provide any other step or replace the unit if necessary.