Yea, looking like solution #1 may be the way to go. I’ll probably swap out the 24V PSU that I have with a 12V one from another project. There are more octocuplers (logic level converters) for 12V to 5V.
$14 will be cheaper and less hassle than changing mobo’s.
Ultimachine still hasnt seemed to respond to your open git issue. Kinda seems like we should be able to get some PWM pin if they get off their duff…
Stupid question, but I cant seem to find what the connector type the fan block is on the Archim board. Any idea what those connectors are called/spec’d?