That is indeed the branch. Totally meant to link to it in my comment, and then got pulled away from my desk and forgot.
There were some weird things on that branch with the new clock tree, but I think most of it was the build I was using didn’t tell the HAL what frequency the HSE was (which is now in the CFLAGS). But it’d be worth running some tests on the external memories, and making sure typical things still function as expected (audio, adcs, etc.).
I’ll try to get this added into the modern libdaisy ASAP. I want to compare power consumption between 400/480 as well so we can make it optional (if it matters). Though at some point I want to add some more in-depth configuration of clock speeds to the PAI make this a bit more power-friendly for lightweight DSP that might want to run on a battery.