Unix and Linux → Framebuffer 1680x1050

Hi folks!

I've been searching for a couple days and finding very little on how to solve my framebuffer issue. I just picked up a new Samsung SyncMaster 225BW monitor from NewEgg with 1680x1050 native resolution which is not supported by LILO in Slackware 12. The monitor is awesome but that's another topic! I currently have the framebuffer set in LILO at 1280x1024x256 which is acceptable. I would prefer full resolution using LILO, not Grub, to do it. BTW, my nVidia 7600GS card does just fine with 1680x1050 in the X server thanks to the nVidia X Server applet added to my KDE menus.

The 1680x1050 resolution is not one of the selections for LILO so how would I go about adding it? Do I put a new entry in the /etc/fb.mode file for LILO to find? If that is the solution how would I determine what the fb.mode entry values should be?

This has me stumped and I'm hoping someone has "been there, done that" and can provide guidance. TIA!

1440x900 is a valid frame buffer size and it's the same ratio as yours so maybe that would be a close compromise?

»en.wikipedia.org/wiki/VE ··· tensions

*edit
Looks at this too, maybe you can just calculate and use the proper number for your resolution.

Thanks for your reply. I found the same Wikipedia entry and it helped me realize that this was somehow possible but didn't give me enough to actually do it. The Gentoo splash link also confirms it's possible.

I still think this has to do with the /etc/fb.modes entries which I'm clueless on how to generate the proper values for the 1680x1050x256 mode. Here is a sample of a mode listed in my /etc/fb.modes file:

#
#1280x1024, 43 Hz, Interlaced (80.00 MHz dotclock)
#
#HorizontalVertical
#Resolution10241024
#Scan Frequency50.000 kHz87.03 Hz
#Sync Width1.000 us0.100 ms
#10 chars10 lines
#Front Porch1.000 us0.500 ms
#10 chars50 lines
#Back Porch2.000 us0.650 ms
#20 chars65 lines
#Active Time16.000 us10.240 ms
#160 chars1024 lines
#Blank Time4.000 us1.250 ms
#40 chars125 lines
#Polaritypositivepositive
#
 
mode "1280x1024-43-lace"
    # D: 80.00 MHz, H: 50.000 kHz, V: 87.03 Hz
    geometry 1024 1024 1024 1024 8
    timings 12500 160 80 65 50 80 10
    laced true
    hsync high
    vsync high
endmode
 

Clear as mud to me!

There is a man page for fb.modes. I'm not trying to be snide, just pointing it out in case you didn't realize it existed. The man page may give you more insight on how to create your own entry.

No offense taken. I had not looked at that man page but I had looked at "man fbset" which near the top declared to be "out of date". I'll look into the rest of the fb man pages and see if they help me piece this mystery together. Thanks!

You should just be able to give the kernel the boot option vga=865 or vga=0x361 for 1680x1050x246.

I see you're trying to get lilo not the boot at this res. This would have to be a lilo specific config I guess? The lilo.conf should take the vga=865 line to set the default resolution for lilo. I think it uses vga=normal by default.

That's what I thought in the beginning too. I entered vga=865 in my lilo.conf and reinstalled LILO only to have framebuffer freak out and ask me to choose from the available resolutions. The choices framebuffer gave me matched the values in the /etc/fb.modes file.

I believe I need to create a new entry in /etc/fb.modes like my earlier post with the specific settings for 1680x1050x256. Then I should be able to pass vga=865 to the framebuffer. I might be going about this all wrong but I'm surprised that others haven't run across this before with their wide screen displays.

Here's a cool command that might get me a little closer. It helps me figure out what values would need to go into an entry in /etc/fb.modes. How I reference it with a vga= line in lilo.conf is beyond me at the moment.

root@slacker:~# gtf 1680 1050 60 -f
 
mode "1680x1050 60.00Hz 32bit (GTF)"
    # PCLK: 147.14 MHz, H: 65.22 kHz, V: 60.00 Hz
    geometry 1680 1050 1680 1050 32
    timings 6796 288 104 33 1 184 3
    hsync low
    vsync high
endmode
 
root@slacker:~#