Bug#700598: scrambled/torn display, booting wheezy weekly amd64 CD on L850/046
On Fri, Feb 15, 2013 at 07:53:01AM +1100, Neale Banks wrote:
>
>Package: installation-reports
>
>Attempting to boot the Wheezy weekly amd64 CD of 2013/2/11 on a new
>Toshiba L850/046 (in EFI mode, secure boot disabled) results in
>scrambled display.
>
>The machine initiates boot from the CD, displays 'Welcome to GRUB!'
>then 'Warning: "prefix is not set'.
>
>Then the display is scrambled (like video "tearing") and confined to the
>upper approx 40% of the screen.
Bugger. :-(
I've tweaked the graphics mode selection recently to go for 800x600 by
default to try and fix this problem. On some machines (notably a
Lenovo laptop I had access to), 640x480 doesn't work reliably. On your
Toshiba it sounds like 800x600 is a problem. I've switched to
hard-coding the graphics mode as grub's own auto-detection of graphics
modes seems less than reliable in the current code. :-(
Neale, could you try the following for me and tell me what happens
please? I need you to type the following (blind!) at the corrupt
display:
"c" (call up a grub command line)
"terminal_output console" (switch to text-mode output, you should
now get visible text output)
After that, the following would be useful too:
"videoinfo" (will print the video capabilities of
your machine)
"set gfxmode=640x480" (try a different resolution)
"terminal_output gfxterm" (go back to graphic-mode output)
"<ESC>" (go back to the menu, now in 640x480)
I'm hoping that the 640x480 mode might work better for you. Whether it
does or not, the videoinfo output would be very useful if you can note
that down for me.
--
Steve McIntyre, Cambridge, UK. steve@einval.com
Google-bait: http://www.debian.org/CD/free-linux-cd
Debian does NOT ship free CDs. Please do NOT contact the mailing
lists asking us to send them to you.
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