Lime2 DRAM: 0 MiB error

[bitwelder]

Hello,

I have a Lime2 (rev B) board. It was running OK with only ethernet cable and SATA SDD plugged. Power via a 5V 2.5A PSU. No problem whatsoever.
Then I had to power down the unit to adjust the shelf it was sitting on.

Unfortunately after that I wasn't able to boot up the board again, only sign is the red power LED, but no green LED and no activity.
Only once in 20-30 attempts I was able to boot up the Lime2.

I have then plugged a TTL-serial-to-USB converter, launched minicom, powered again and... this is what I get:

Code Select Expand

U-Boot SPL 2014.04-10706-g36080eb-dirty (Oct 08 2014 - 11:45:32)               
                                                                               
Board: A20-SOM                                                                 
                                                                               
DRAM: 0 MiB                                                                     
                                                                               
### ERROR ### Please RESET the board ###      
RAM chips got killed?
As I was able to boot again the board at least once, I wonder if the problem is somewhere else, perhaps some of the voltage regulators are fishy. So far I only tested that at the TVS protection diode just behind the power jack there are 5.0V so PSU should be OK. I inspected the PCB with a loupe and I don't see any shorts or bent pin.

Any suggestion on how to troubleshoot what's wrong here?
Thanks

EDIT: wait a sec... why does it says Board: A20-SOM if it's a OLinuXino Lime2? Let's try to flash a different u-boot config...