First cable for Euler Bus power done!

[MarkHaysHarris777]

The MicroUSB connector has a max rating of 1.8A, and a lot of MicroUSB leads are pretty wimpy (wires too thin, poor conductivity contacts) , and will not provide the Pine64 with the necessary power when it is loaded up, leading to file corruption, random brownouts, reboots, etc. This cable plugs into the euler bus, and powers the pine64 via the power pins there.

And the USB Plugs into....?

An appropriately rated power supply (with female USB connector).

Ideally 1.8A or higher? How many amps is too many amps?

Ideally 2 amps and up. An amp is a unit of current. In getting the Pine to work, a power supply with 'too many amps' isn't an issue, only one that doesn't allow enough amps - enough units of current - to flow into the device. The amp rating on a power supply shows how many amps the unit is capable of providing - it doesn't force the connected device to accept all the amps it can provide. The device withdraws only what it needs.

I must also add ( with all above ) that its also about how 'clean' the supply is;  that is, how stable the 5.1v DCIN is as varrying amounts of current are pulled from the PSU. If there is a ripple in the DCIN ( as you might see on a scope ) or if the 5.1v fluctuates dramatically as current is pulled from the supply the pine board is going to have problems. 

Specifically, if you plug that usb connector into some notebook computers there will NOT be adequate stable voltage for the current range of the pine board, and the pine board is liable to brown out or not bootup. On the other hand if you plug the usb connector into a good usb powered hub the pine board ought to do quite nicely. 

I would recommend building a 12v system ( dc-dc converter 12v-->5v ) with a PI-filter the output of which is a female usb connector.  Then you can plug the cable above into that output and have a very good clean supply from which to power your pine board ( all of my pine boards are powered this way ).