I have a Octominer B8Plus motherboard and it works fine with the mSATA SSD, but I really need to boot off a USB thumb drive with Ubuntu on it. I can't get this to work.
It just says "Reboot and Select proper Boot device or Insert Boot Media in selected Boot device and press a key".
Screenshot:
https://imgur.com/BMef7iLHello in the options for system start, you have the option to start upload from usb? As an option there may be a problem in the usb.