I recently started a new project, and the quickest way to get an Arduino Nano delivered was to get a "knock-off" board. The specific one I used was purchased from Amazon:
Everything looked normal when it arrived, but I could not get the Arduino IDE to recognize the device via USB (the port menu remained greyed out in the IDE). It turns out this board uses a alternate communications chip which was missing drivers on Windows 10.
Original ATmega328P CH340 chip is used. Improved new version CH340G Replace FT232RL.
After a bit of searching, I found link on SparkFun to download/install the CH340 drivers. After the drivers were installed, the Arduino IDE recognized the Nano and all was right with the world...
