There is no specific board that is the best for setting up a Lightning Network (LN) node, but there are some important factors to consider when choosing a board:

Processing power: The LN node requires a moderate amount of processing power, so a board with a powerful processor would be ideal.

Storage: An LN node requires a significant amount of storage for storing the network's database. A board with at least 256 GB of storage is recommended.

Network connectivity: It is important for the board to have good network connectivity in order to maintain good synchronization with the LN network.

Power consumption: An LN node can consume a significant amount of energy, so it is important to choose a board with low power consumption.

Based on these factors, some boards that may be suitable for setting up an LN node include: -Raspberry Pi 4 -Odroid XU4 -Intel NUC -Rock64

However, it is important to verify if it meets your specific requirements before making a purchase.