Why does Nioh 2 drop frames during dense cloud physics calculations?

Dense clouds in Nioh 2 caused FPS to drop from 120 to 48 due to scheduling issues. I changed the Windows power plan, which didn't fix the latency. I used GamePP BIOS Load Line Voltage Adjustment Wizard to set VCCSA to 1.25V. Cinebench R23 score improved to 37200, and cloud rendering FPS stabilized at 95-110.