One of my cubes has shut down - I happened to be sitting right by it and heard the relay click. Red light and bottom pwr light are dark, fan twitches but does not spin. I've swapped in a power supply that has been running two other cubes, and I get the same symtpoms.
I opened it up and checked the board - I see no evidence of overheat. I shorted the two power relay leads and all the lights come one, but with no fan I'm not inclined to run it for more than a few seconds that way.
Is it possible that the fan is just bad? I don't have a similar one to swap in tonight.
While preparing to order a fan, does anyone know what RPM the stock fans run at? I see another post about a 2900 rpm 90mm fan, but I'd rather not have that noise level. I guess more importantly, does anyone know what RPM the device wants to see?
Other thoughts about what could cause this?
Try swapping fans between the two Cubes to determine if it is the fan.
I think I saw in a previous post that the fans were variable speed, search back in this thread (I have no idea how to do that, help anyone?). They have there conductors, one is a tachometer (speed) signal so the Cube can control the speed with the feedback.
My guess is that the fan failed, the controller no longer saw a speed signal and shut down the mining power relay.
You would want to get a fan with a tachometer (three wire connector) and either a ball bearings or fluid (rifle) bearing for lower noise and longer life. The fan size is 120mm by 25mm.