Re: How to activate VESA mode on boot-up?

[Frank Lin PIAT <fpiat@klabs.be>]

On Sun, 2009-07-05 at 21:59 +0200, Robert Latest wrote:
> 
> Long story short, when I put "vga=ask" in grub's menu.lst, I can't
> enter anything but the 80-by-something modes. I've searched the Net up
> and down, have tried the 0x30... modes in hex, in decimal , with the
> '0x' and without ... nothing. The kernel simply doesn't know any
> additional modes (and doesn't list them. either).

Assuming you are running a Debian kernel,

Quoting /usr/share/doc/linux-doc-2.6.26/Documentation/kernel-parameters.txt.gz
> vga=            [BOOT,X86-32] Select a particular video mode
>                         See Documentation/i386/boot.txt and
>                         Documentation/svga.txt.
>                         Use vga=ask for menu.
>                         This is actually a boot loader parameter; the value is
>                         passed to the kernel using a special protocol.


The videomodes are then documented in 
  /usr/share/doc/linux-doc-2.6.26/Documentation/fb/vesafb.txt.gz, especially:
> So the table for the Kernel mode numbers are:
> 
>     | 640x480  800x600  1024x768 1280x1024
> ----+-------------------------------------
> 256 |  0x301    0x303    0x305    0x307
> 32k |  0x310    0x313    0x316    0x319
> 64k |  0x311    0x314    0x317    0x31A
> 16M |  0x312    0x315    0x318    0x31B

I usually have vga=791 (the decimal for 0x317),  to use 1024x768.

Hope this helps.

Franklin

Note: xen dom0 doesn't support framebuffer.