LIV's performance is dependent on two things: your own hardware and how well optimized the game you're capturing is.
Minimum specifications for LIV
GPU: NVIDIA 2060 or AMD equivalent. CPU: latest Intel i5 or AMD equivalent.
A minimum spec system might suffer when trying to capture less optimized or more graphically demanding games.
Recommended specifications for LIV
GPU: NVIDIA RTX 3070 or AMD equivalent. CPU: Intel i7 or AMD equivalent.
Tips
Check out the How to improve performance with LIV article here