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I've just gotten 3 new systems, with Nvidia GTX 660 graphics, Z77 chipset and AMI UEFI BIOS.

I've installed Ubuntu 12.04.2 LTS from the Alternate Installer in order to install onto an encrypted LVM with boot time password.

This worked OK-ish - some graphical corruption in the bootloader on first boot, but I was able to type in my disk password and boot into X.Org. This was using the default nouveau driver. This driver is not stable with this hardware - moving a window rapidly around the desktop caused X.Org to crash. This behaviour is consistent across all three systems, so it is very unlikely to be a hardware issue.

So I installed nvidia-current using the Additional Drivers settings applet and rebooted. Thereafter, booting up the machine was unreliable: sometimes, immediately after the BIOS finished, it would show the message:

error: no video mode activated.

before showing the GRUB2 boot menu (in fact, this text is shown above the American Megatrends logo, which has not been cleared from the screen); other times, it got far enough to show the menu. But upon selecting the normal boot from the menu, just a blank screen is shown.

I inserted the following (from here) directly into the GRUB2 menu entry editor

insmod efi_gop
insmod efi_uga
insmod font
loadfont ${prefix}/unicode.pf2
insmod gfxterm
set gfxmode=auto
set gfxpayload=keep
terminal_output gfxterm

This got me some boot text and an encryption password prompt, but X.Org then complained that the graphics were too low-end to continue. So this was a dead end.

After much head-scratching, I finally realized that I could type my encryption password blind into the blank screen, and boot would proceed. But this means I have no text-mode terminal. In X.Org, when I type Ctrl+Alt+F1, I just see a blank screen.

I know (from past experience and looking at the kernel logs from dmesg) that the Nvidia proprietary drivers don't like graphics mode boots. Normally the cure would be nomodeset on the kernel command line, but that doesn't work here. Nomodeset still results in a blank screen.

What is the correct procedure for setting up a text mode boot with 12.04.2 on UEFI and Nvidia hardware, such that a boot-mode password prompt is visible?

PS: This page suggests that I should be using a different boot loader and that GRUB2 is a poor choice for UEFI systems, but I don't really want to mess around with replacing the boot loader if I can help it.

PS: /sys/class/graphics/fb0 does not exist; I interpret this as no framebuffer driver being loaded at all. From other research, I believe a framebuffer driver is necessary for EFI boot text support, as there is no fallback to BIOS text output (and so vga_text doesn't work). I'm starting to suspect I should be looking for a framebuffer driver that works with nvidia-current binary drivers.

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