The switch is there even if XPU is not supported on Macos at all.
So I flipped it and am very curious what is going on behind the scenes, becaus it clearly looks completely off but it is also doing something and it seems "faster" at whatever it does than Karma CPU.

Very curious to find out more.

Karma XPU has two components - a CPU engine and a GPU engine (hence XPU).

The CPU engine is what you're seeing on Apple silicon.

johnmather
Karma XPU has two components - a CPU engine and a GPU engine (hence XPU).

The CPU engine is what you're seeing on Apple silicon.

oh ok thanks!

is that why it seems faster? the CPU part of XPU being slightly faster than Karma CPU itself?

Yes. XPU does not have the same feature set as Karma CPU, so it can be faster.