Low FPS in dungeons, World Boss LFGs, BGs

I bought a new machine in Dec 2019 for Shadowlands only to discover that when in dungeon encounters, World Boss raids, PVP, essentially any content with more than 3 avatars (player or NPC) preforming actions my FPS drops to 20-14 from 100-130. I’ve recycled through all my adding (even ran a heroic with no addons from muscle memory and still they drop through the desk. Adjusted all my setting way down. Drivers and windows (yuck) are all current. I’m not sure what to do. I will say that is makes my game experience poor and I feel it bars me from enjoying certain content I really enjoy. Please help.

Update:
Discovered the issue. Machine power options were set to power saver mode. Switched to high performance power settings and boom. Runs like a dream.