I’m just using a 5volt, 1.5amp power supply from a wall transformer that is connected to my pca9685, for now. I tried a more powerful 2amp transformer that seems to have helped, but it feels like more art than science sometimes... I’m trying a 7.4 volt 2S LIPO tomorrow and will have to post on the results. I’m uncertain if it’s a malfunctioning pca9685 or cheap servos or even odd timing from the RPi3b+, so I’ll see if I can methodically isolate the power(amps anyways) in efforts this week.
I have found more powerful servos but they’re unfortunately very expensive. $35-50 per servo vs $6.50 per servo (existing Mgr996 on amazon). I spent several hours researching dc geared motors and stepped motor alternatives, but they all appear to be at least $65+ each for non servo options (And considerably more torque but far slower RPMs for trade-off).