You don't need two PC's to stream to be a successful streamer, but it does have 2 big advantages:
Mongraal gained fame as the youngest professional Fortnite player. He signed with the e-sports collective Team Secret and in 2019 he joined FaZe Clan.
Mongraal uses the Acer XF250Q and the BenQ ZOWIE XL2540 gaming monitor.
For gaming, Mongraal uses a Intel Core i9-9900K CPU with a MSI GeForce RTX 2080 Ti GPU. He uses a ASUS ROG Strix Z370-E Gaming motherboard. Mongraal uses a Samsung 970 EVO 500GB SSD for storage.