Here's the system requirements for Black Ops 4's battle royale mode beta
https://www.pcgamer.com/heres-the-system-requirements-for-black-ops-4s-battle-royale-mode-beta/
With the PC beta for Call of Duty: Black Ops 4’s Blackout battle royale mode only a few days away, Treyarch’s released minimum and recommended system requirements. They’re almost the same as they were in the multiplayer beta, not surprisingly, so if you were fine then, you should be all set.
CPU: Intel Core i5 2500k or AMD equivalent