I hope it isn't firmware. Bought a 2nd hand unit from a guy here on Carb. Screen was working before shipping, but after assembly on my side the screen just stays white. Clicking the button/knob still makes the sound so I don't think it is the mobo. I'm thinking the ribbon cable or the screen.
When you switch it on you briefly see something that could very well be the Ender logo, but then it goes all white and stays that way.
Drove out to stellies for a replacement cable but the guys at Micro Robotics didn't have the right cable. The one listed as in stock on their site is, erm, not the right cable.