initializing SDRAM Fail on Pine A64+ with 2GB RAM

[tkaiser]

Is there a way to set lower DRAM frequency to see if that fixes it?

A successful DRAM initialization should read "DRAM zq value: 003b3bbb" instead. And since this happens even before u-boot is loaded I would suspect you're not able to adjust any values here.

Did you try to power the board through the pins on the Euler connector? And use the serial console from the EXP header pins (since then they can't backpower the board which leads to all sorts of strange behaviour and might be related to the problem you're running into)