ASIC device usually has much better mining performance than graphics card. It is more energy-saving and has a much higher hashrate.
The MicroBT Whatsminer M21S was produced by MicroBT and released in 2019. This miner consumes 3360W, producing 56.0 Th/s of hashrate with the sha-256 algorithm, which makes this device almost (if not at all) useless. We do not recommend buying this device for mining nowadays.