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sblantipodi
31st October 2007, 01:54 PM
Hi,
I've got an nvidia 8600M GT using Fedora7 and a vanilla 2.6.23 kernel.

I want to enable framebuffer but my native resolution is 1280x800...
Is there someone who can help me setting this resolution on framebuffer please?

Thanks!
Davide.

LostSon
1st November 2007, 04:35 PM
It looks like this thread here may help you

http://www.linuxquestions.org/questions/slackware-installation-40/laptop-acer-1690-1280x800-resolution-343258/

Looks like it is gonna take some work.

sblantipodi
1st November 2007, 04:42 PM
It looks like this thread here may help you

http://www.linuxquestions.org/questions/slackware-installation-40/laptop-acer-1690-1280x800-resolution-343258/

Looks like it is gonna take some work.

I haven't find anything about framebuffer in that thread. :confused:

sideways
1st November 2007, 05:43 PM
I could never get this to work with vesafb or radeonfb, so perhaps it's not possible with nvidiafb either.

Instead, you can at least improve the default console resolution (I assume you really mean this, rather than xwindows resolution) to 1024x768 32bit , using the vesa framebuffer by adding "vga=0x317" to the kernel line in /boot/grub/grub.conf. That used to look ok on a 1280x800 laptop I used to use. I now have a 1280x1024 screen and use "vga=0x31B"

http://www.mjmwired.net/kernel/Documentation/fb/vesafb.txt

sblantipodi
1st November 2007, 06:29 PM
I could never get this to work with vesafb or radeonfb, so perhaps it's not possible with nvidiafb either.

Instead, you can at least improve the default console resolution (I assume you really mean this, rather than xwindows resolution) to 1024x768 32bit , using the vesa framebuffer by adding "vga=0x317" to the kernel line in /boot/grub/grub.conf. That used to look ok on a 1280x800 laptop I used to use. I now have a 1280x1024 screen and use "vga=0x31B"

http://www.mjmwired.net/kernel/Documentation/fb/vesafb.txt

I know 0x317 is better than nothing but I want 120x800 native resolution :(

sideways
2nd November 2007, 03:12 PM
Well now it appears to work, at least on the wife's laptop.

I got it to work with the default vesafb using vga=872. This is on a Toshiba laptop using an intel graphics chip.

I used vbetest to find the graphics mode, if you are in xwindows switch to a console using ctrl+alt+f1, then (as root)


yum install vbetest
vbetest
VBE Version 3.0
Intel(r) 82945GM Chipset Family Graphics Chip Accelerated VGA BIOS
[352] 1280x800 (256 color palette)
[353] 1280x800 (5:6:5)
[354] 1280x800 (8:8:8)
[358] 1280x800 (256 color palette)
[359] 1280x800 (5:6:5)
[360] 1280x800 (8:8:8)
[261] 1024x768 (256 color palette)
[279] 1024x768 (5:6:5)
[280] 1024x768 (8:8:8)
[274] 640x480 (8:8:8)
[276] 800x600 (5:6:5)
[277] 800x600 (8:8:8)
[257] 640x480 (256 color palette)
[259] 800x600 (256 color palette)
[273] 640x480 (5:6:5)
Type a mode number, or 'q' to quit -

try the various modes, 360 worked for me. Then add 512 to that number, 360+512=872, and use that in your vga parameter passed to the kernel at boot time. :)

It does look quite a bit sharper, although some people may find the font size a little small.

You might want to increase the console scroll buffer (shift + pgup/pgdn), do that by adding something like 'fbcon=scrollback:128K' to the kernel line.

sblantipodi
2nd November 2007, 07:19 PM
Well now it appears to work, at least on the wife's laptop.

I got it to work with the default vesafb using vga=872. This is on a Toshiba laptop using an intel graphics chip.

I used vbetest to find the graphics mode, if you are in xwindows switch to a console using ctrl+alt+f1, then (as root)


yum install vbetest
vbetest
VBE Version 3.0
Intel(r) 82945GM Chipset Family Graphics Chip Accelerated VGA BIOS
[352] 1280x800 (256 color palette)
[353] 1280x800 (5:6:5)
[354] 1280x800 (8:8:8)
[358] 1280x800 (256 color palette)
[359] 1280x800 (5:6:5)
[360] 1280x800 (8:8:8)
[261] 1024x768 (256 color palette)
[279] 1024x768 (5:6:5)
[280] 1024x768 (8:8:8)
[274] 640x480 (8:8:8)
[276] 800x600 (5:6:5)
[277] 800x600 (8:8:8)
[257] 640x480 (256 color palette)
[259] 800x600 (256 color palette)
[273] 640x480 (5:6:5)
Type a mode number, or 'q' to quit -

try the various modes, 360 worked for me. Then add 512 to that number, 360+512=872, and use that in your vga parameter passed to the kernel at boot time. :)

It does look quite a bit sharper, although some people may find the font size a little small.

You might want to increase the console scroll buffer (shift + pgup/pgdn), do that by adding something like 'fbcon=scrollback:128K' to the kernel line.

Thanks for your reply.
With my GeForce 8600M GT doesn't work :(
I tryed vga=872 but it doesn't work. :(

vbetest returns this error:
can't get vesa (VM86 failure)

Please help.

sblantipodi
2nd November 2007, 07:41 PM
yea :)
I solved with vga=864

thanks!

sideways
2nd November 2007, 09:38 PM
yea :)
I solved with vga=864

thanks!

cool, that corresponds to mode 352 which with the vesa bios extensions on my intel chip is 1280x800 with a 256 palette (rather than (8:8:8) which is full 24bit color)

Maybe your nvidia bios limits the number of colors in this mode, or maybe that mode isn't 256 color mode on your bios.

Luckily modern gpus seem to support this vbe mode.

There is a nice wikipedia article on VESA Bios Extensions (http://en.wikipedia.org/wiki/VESA_BIOS_Extensions) if you're interested, but the mode numbers given there don't seem to match what we are using (I'm trusting that vbetest is correct here)

sblantipodi
2nd November 2007, 11:02 PM
cool, that corresponds to mode 352 which with the vesa bios extensions on my intel chip is 1280x800 with a 256 palette (rather than (8:8:8) which is full 24bit color)

Maybe your nvidia bios limits the number of colors in this mode, or maybe that mode isn't 256 color mode on your bios.

Luckily modern gpus seem to support this vbe mode.

There is a nice wikipedia article on VESA Bios Extensions (http://en.wikipedia.org/wiki/VESA_BIOS_Extensions) if you're interested, but the mode numbers given there don't seem to match what we are using (I'm trusting that vbetest is correct here)

no, with my cards 352 corresponds at a 24bit 8:8:8....
Fedora tell me: "360 mode".