Difference between these two NodeMCU boards?
The top one is a real NodeMCU version 1 board (ESP-12E module).

The bottom one is a knock-off copy - looks like the same module on it.

The biggest difference is the USB interface. The real one uses a CP2102 USB to UART bridge. The copy uses a CH340G chip.  The CH340G is notoriously unstable and liable to die at a moments notice.  The CP2102 is far more reliable.  I recently accidentally nuked a Wemos D1 Mini pro which has the same CP2102 on it with 12V.  It took out the voltage regulator. It took out the ESP8266 chip.  I replaced both those, and the CP2102 was proved to still be working fine. More than could be said for a CH340G - glance at one of those wrong and they die.