Ah thanks.
M3 is 3mm and M4 is 4mm. They just use the Mx rating for screws. Maybe ill try with both. Its best if the screw attaching the heatsink is as snug as possible...
Nope, stay with M3 screws. For two reasons:
- drilling tolerances
- thermal expansion of the PCB.
Thanks. Any tips for mounting heatsink? Would the PCB take the weight of aliminium heatsink if the pcb is mounting on hex spacers?