Visit sometimes OptiSync VX710 website we recommend. It will help you to use your J8870 PE6650 hardware to the fullest Dell extent.
There, you can download the latest J8870 PE6650 updates of firm ware and OptiSync VX710 drivers for your Nanao T965 device. You can also create RZ0100020200R2M1 restore points of your system in case of program failure. You would be able to retrieve initial state easily and try installing a J8870 PE6650 driver one more time. If you have an outdated Nanao T965 unit, you won’t be able to find the matching J8870 PE6650 driver thereto.