On 20/06/2018 12:35, Martin Gregorie wrote:
> - a USB power supply (2A capability for an RPi 3)

The 3+ seems to be pickier aka. more demanding. I have a couple of
adapters from Modmypi with a flip switch in the cable for easy on/off,
which *should* be good at specified 5.1 V 2.5 A, but no go with my 3+.
The official adapter works fine, even with a usb hdd as startup disk.

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