I bought a latest Dell XPS 8900 desktop with Windows 10 Pro system a month ago, first time I switch on PC it went to BIOS setup instead of Windows 10. So I had to press F12 button to run one time boot setup to change the configuration, and chose Windows Boot Manager option to go into OS.
After I finished setting up the system, I found every time I start PC, it always goes to BIOS setup.
Then I went to BIOS setup to check the boot sequence, the result is under UEFI mode, only one option 'Windows Boot Manager' is available. But my friend's Dell PC with same BIOS version shown one extra option which is the hard drive.
Dell customer service has sent me a OS CD to reinstall the system, but failed.
I would ask you to wipe all the partitions and then perform a clean installation of operating system.Also confirm if you have performed the dell hardware diagnostics on the system by pressing the F12 key on system startup then start the system.
And provide us the service tag or the reference no of the case via private message so that we can all the troubleshooting steps performed by tech support.
DELL-Jennifer K Social Media and Community Professional #IWork4Dell