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I'm totally new at Unbutu/Lynux.

I've installed the server on an old pentium 4 with 1gb of ram. The problem is that the monitor (Samasung LED 3d TV through HDMI) gives the message this resolution isn't supported. So I can't see if everything is working. It should work at 800*600 at 32 bit 75 Hz. Can anyone help me to change the resolution at bootup.

For your information, U don't know how to get to a save mode, edit cfg files and so on. I've read a lot of the posts on this site, but I can't do anything with them.

Please help me.

marked as duplicate by Tim, Eric Carvalho, Eliah Kagan, muru, αғsнιη Oct 24 '14 at 7:56

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You can either use the xrandr command-line tool this shows you the names of different outputs available on your system (LVDS, VGA-0, etc.) and resolutions available on each.

sudo su 

Or You can direct xrandr to set a different resolution using the following command

sudo su 
xrandr --output VGA --mode 800×600 --rate 75

Due to buggy hardware or drivers, your monitor's correct resolutions may not always be detected. If the mode already exists, but just isn't associated for the particular output using the following command

sudo su    
xrandr --addmode VGA 800×600

There are several ways to make xrandr customizations permanent from session to session:

1- A user's ~/.xprofile file is executed on Xorg startup if it exists and is executable. You can copy and paste xrandr command line strings into this file so they're executed when you log in.

2- Both kdm/gdm/lightdm have startup scripts that are executed when X is initiated. In either case, you can paste in an xrandr command line string into one of these scripts.

3- xorg.conf, see man xorg.conf for full details on how to use an xorg.conf file.

Check man page from here: http://www.x.org/archive/X11R6.8.0/doc/xorg.conf.5.html

  • Thanks for the advice. I’d like to try out your answer, but the problem is I can't see anything. ;-) The monitor stops about a second after the boot/bios screen. Is there a smart key I can use to jump to the command line at boot up, so that I can enter those commands? An if so, do I need to loggin and/or download programs (need network acces?) and how do I do that? I've been at the grub commandline and at the root commandline through the recovery mode. But I actually don't know witch one I should be... Sorry, but I meant it when I wrote I was new at this. – MDF Sep 2 '14 at 5:16

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