[rixrax]

But what about the heat sinks / fan when you mount the m2 on top? Especially /w Pi 5, to get more perf out of it, it presumably should have a sizeable heat sink complete with the fan?

[distances]

The Active Cooler part (that contains a heatsink too) fits well under the HAT.

[jsheard]

The fan won't do much if there a second PCB stacked right on top of it though, unless there's cutouts for it.

[0x073]

A covered fan is not very clever and the rp5 need active cooling.