nfs hot pursuit 2 low fps until i put overclock

[Pimenov]

Why does NFS HP2 run at 15FPS with default settings but overclocking to 40% speeds up to 50FPS?
Xiaomi Redmi Note 9 Pro

[JosJuice]

That's underclocking to 40%, not overclocking to 40%

The way this game behaves performance-wise is kinda weird, because on console, the framerate is limited by how fast the GPU is, and the game usually ends up running at around 30-40 fps. Dolphin emulates a much faster GPU than what a real GameCube has, increasing the framerate that the game is "supposed" to hit, which makes the game a lot more demanding to emulate than if it had been running at the same framerate (from the perspective of emulated time) as on a real GameCube.

As for why underclocking the emulated CPU fixes it... I guess it makes it so that the CPU is the bottleneck instead of the GPU? And once you get to that point, the "target" framerate (that is, Dolphin's target, not the game's target) will get lower the more you lower the CPU clock. Actually, I'm not sure if that make sense... Going from 15 FPS to 50 FPS is pretty extreme, assuming you truly mean FPS and not VPS. (I'd assume you do mean FPS, since the FPS counter on Android doesn't show the VPS.)