I got my Dell 3551 with ubuntu today.  I am facing a similar situation.  If legacy mode booting is enabled, then something happens to uefi firmware boot process.  I am trying to understand how uefi booting process works along with the EFI System Partion (ESP).   One good place is -  www.happyassassin.net/2014/01/25/uefi-boot-how-does-that-actually-work-then/ Once something wrong happens dell recovery kicks in and reinstalls everything.  Another problem I am facing is that the process to create a recovery media on usb flash drive fails. I have used different usb pen drives but if fails with all of them.  The recovery flash drive would come in handy if computer is required to be reset to factory state.   Please inform about your experience with that.  I am wondering which partition used by dell recovery program. Also inform if drivers for Windows are hidden somewhere on the hard disk.  Thanks.
Inspiron 15 3551 BIOS Rev A00 Ubuntu 14.04 preinstalled by Dell. My laptop is brand-new. I went through the initial setup in about 15 minutes. It all worked fine. I rebooted a few times without problem. At this point, the boot options are (if I hit F12 at startup): Tittle: Boot mode is set to: UEFI with Legacy OPROM: Secure boot: off LEGACY OPTIONS: Hard Drive UEFI OPTIONS: PEBOOT ubuntu HDD1 - UEFI OS(TOSHIBA )  Please note that I never actually used the boot menu. I just used the default. After a few days, I wanted to change how the function keys worked, so I rebooted and went in to the BIOS, changed that setting, then selected "Save Changes and Reset". The laptop restarted, but couldn't find the right boot disk (or partition or whatever -- not sure of the exact terminology). An error flashed on the screen: Could not open "\EFI\BOOT\fallback.efi": 14 Then, the only choice I'm given is to boot from the recovery partition, which forces me to do a full reinstall -- 15 minutes plus loss of all data. If I hit F12 at startup while the laptop is in this state, the boot options are just like above, except missing the 'ubuntu' option, like so: LEGACY OPTIONS: Hard Drive UEFI OPTIONS: PEBOOT HDD1 - UEFI OS(TOSHIBA )   I ran the ePSA Pre-boot System Assessment, and it indicated no problems. This problem is reproducible. I have walked through the entire sequence 3 times. So, what gives? How do I change BIOS settings without losing my OS partition?  Thanks, Joel
Inspiron 15 and Ubuntu 14.04: Changing BIOS settings deletes 'ubuntu' partion