This topic is probably not Ubuntu related, but any UEFI linux distro. What I 
found out so far:
Notebook: Samsung series 3 NP300E5C-A05DE (German), BIOS-ID: RAC, current 
version: P05RAC

Installed Linux Mint 13, MBR mode. Later converted to GPT/UEFI - all
seemed ok. Device booted ok, but then I recognized, that I was unable to
enter the BIOS Setup with F2 anymore.

What still works: F3 to boot from CD, FAT32-Stick with EFI-Shell v1.0 saved as 
\EFI\BOOT\BOOTx64.efi
(2.0 does not work even if BIOS version is UEFI 2.31)

My fix: CD with WinPE, then flash BIOS (if using Samsung Flasher need to
remove version check is BIOS is current, or directly use WinFlash)

What's causing this?

After I fixed my BIOS I tried to re-enable UEFI booting my linux using
"efibootmgr", which instantly messed up my BIOS again (but I need stuff
like that twice...)

So I messed around with HexEdit and efishell and found 10 - in words TEN
- efi boot entries within the Samsung BIOS, that are not even shown in
"efibootmgr" - the first Entry is "Setup", second is "Recovery", third
is "CD-ROM" and so on, so it seems like Samsung is misusing those hidden
bootentries for their own stuff, putting the Setup into the first boot
entry, which will be overwritten by efibootmgr - explains why it was
still booting, but unable to enter Setup.

Since I found the key assignments to these entries within Samsung
related BIOS modules, they are responsible for this non-standard stuff.
Thank you, Samsung.

My stuff still does not explain complete bricks like others have
encountered. But maybe the hint with the version 1.0 efishell might
help, or even pressing F3 still helps, if the BIOS is not bricked
completely.

For all the Linux EFI programmers: Those bootentries are there, but only
shown by efishell. Why does the nvram-module in linux not show them?
Maybe there is an unusual way to get them from the nvram - if you could
check them you should be able to avoid these bricks..

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https://bugs.launchpad.net/bugs/1040557

Title:
  UEFI boot live-usb bricks SAMSUNG 530U3C,np700z5c laptop

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