We have the official firmware of the Nexbox A5 android TV. This android TV is powered by ARM Cortex A53 64 bit chipset that runs at 1.5GHz and is backed by Mali 450mp5 GPU.
You can download the official firmware for the android TV from here. Just make sure you download it over broadband connection as it about 680 MB in size.
Before running the Setup program, you need to disable the secure signing of drivers. In windows 8, go to settings in Metro environment > Update > Recovery> Advanced Home> restart now> Troubleshooting> boot Options> Disable the mandatory use of signed drivers.
For windows 10 – Start Menu> Settings> Update and security> Recovery> Under the option advanced Home click restart now> Troubleshooting> Options advanced> startup Settings> Reset> Press 7 or F7 for D to disable mandatory use of signed drivers. The computer will restart and you can install drivers without digital signatures.
Nexbox A5 specs include 2GB of RAM, 16GB of internal storage, wireless a / b / g / n, Bluetooth 4.0, four USB 2.0 connectors, Ethernet, HDMI 2.0a, audio jack, microSD reader and SPDIF cards.