Hallo!
I have a new DB75EN Board.
After i have installed OS the Bios told me that it cannot find a boot device.
I go to boot menu and select the only Hard disk installed, the system boots fine.
After restart of the os i go to Bios and turned off all other boot devices expect of the SSD.
The system told me again that it cannot find a boot device.
I go to boot menu, the only choice is now the SSD there. I select it and system boots.
Why can the system not detect the boot system automatically? 
Thanks for any help!
Harald