Title. In other words, sbc recommended/optimal power supply is 5V4A but I use an 5V3A instead – will it damage or kill the sbc? The reasoning behind this is “an direct undervolting towards the system, for lower power draw and temps”.
Thanks in advance.
I don’t think so, in worst case it will just not work at all. First think is that the recommended requirements are for ‘maximum load’, so as long as you don’t load it too much, it should be ok.
Now I think you will be more concerned about the behavior of the power supply when overloaded. It can go from a voltage drop (which will cause your sbc to reset or shutdown), an output cut or the magic smoke can come out if the supply is wrongly designed. There are minimum risk that the sbc is damaged (0 risk don’t exists) although.