My current setup is the tinkerboard powered by the raspberry pi universal adapter connected to ethernet and a external HDD(Maxtor M3) powered by the Tinkerboard's usb. I have used it very lightly in this configuration (ssh-ing into it and copying some files to the hdd) but from what I have gathered from the information available here this powering setup is inedequate and will lead to problems.
So I want to follow the recommended method and power it through the GPIO pins. I am considering using this or this powersupply. (I realize 10A on the second one is overkill for the tinkerboard, but the price difference from the 3A rated one is minimal and I could find some other use for it in the future). Is any of this a reasonable choice? TonyMac32 warns not to exceed 5.5v but both list a voltage protection range higher than that.
TonyMac32 also mentions using a zener diode and a capacitor to filter power and protect the board from overvoltage. While I have a basic understanding of electronics, I don't know how to make that circuit or the exact values of the components that I would need. Could someone elaborate on how to make this circuit and the difference it would make over plugging straight to the GPIO pins?