“A bootable device has not been detected.”
Or something like that. No BIOS prompt, no F2 settings, nothing.
Don’t panic, yet. It is sometimes fixable. This is a BIOS bug that sometimes happens with the factory flash. Intel has fixed it in newer shipments. But fixing it in your DE3815 will take some effort.
You need at least BIOS 0030 to fix this. Download it to a FAT-format Flash Drive. Connect a wired USB keyboard. You need to be fast with the timing to hit the keystroke correctly. (DE3815 Downloads Page – use the latest BIOS if 0030 isn’t the latest).
Now, you may notice you can’t get into the BIOS with this error. You actually can, but you have to hold the power button for three seconds. However, booting into Visual BIOS will leave you in a bootloop. To be clear, do not attempt to flash DE3815 to 0030 from F2/Visual BIOS.
Here are the steps:
1) Connect power, display, USB flash drive (with 0030) and a wired USB keyboard. Don’t connect anything else.
2) Hold the power button for 2-3 seconds. If you hold it for 4-5 seconds, it will power off. Don’t hold it for 1-2 seconds or you won’t get going. Yes, you may have to do this multiple tries – it’s not easy.
3) Rapidly mash F7 on your keyboard, ideally from the moment you start holding the power button. This takes you into the non-Visual Boot BIOS flash mode.
If successful, you’ll get to a BIOS flash prompt, and select the flash drive, and flash as normal.
Now, one of two things will happen. You’ll be prompted on the next boot to restore Fastboot. Press Y. If successful, your system will be good to go. If that fails, you have a defective NUC.
Hope that helps. In our use of the DE3815 – this is a rare problem. We haven’t had too much luck with Fastboot actually recovering a DE3815 in this state – but we’ve managed to pull one or two out of a bootloop with this.
Console OS will require BIOS 0030 on the DE3815, for other reasons (namely a Video BIOS update).
Not aware of this issue affecting any of the other NUC models.