can't change screen resolution on Dell with Intel video card

[pytheas22]

Hi everyone,

I'm having a really frustating time trying to change the screen resolution on my system, which is a Dell Inspiron 1150 with an i855 graphics card. No matter what I do, it won't change from 1024x768. I'd really like it to be 1280x1024, as I had it in Windows on the same machine.

I've tried changing the monitor type (I've tried both Generic 1280x1024 LCD display and Dell laptop 1280x1024 display) and screen resolution through the GUI available at System>Admin>Display. After I change the settings there, however, it tells me it's updated xorg.conf (which it has), but when I restart X, the screen resolution is still 1024x768, no matter what I had changed it to and apparently no matter what xorg.conf says. Even if I try to just reduce the resolution to a smaller setting like 800x600, it still doesn't change. The Gnome screen resolution configuration panel under Sys>Preferences also doesn't help, as it gives 1024x768 as the only choice, again no matter what xorg.conf says.

As you can see from my xorg.conf file (posted below), the Screen section is definitely configured to support resolutions other than 1024x768. Even if I remove all the entries in the Mode line except 1280x1024, however, it still produces a 1024x768 resolution.

I have 915resolution installed, and if I run the command

# 915resolution 49 1280 1024

I get the positive output

Chipset: 855GM
BIOS: TYPE 1
Mode Table Offset: $C0000 + $29f
Mode Table Entries: 39

Patch mode 49 to resolution 1280x1024 complete

but even after doing that and restarting X, the resolution doesn't change to anything besides 1024x768.

I've tried using both the intel and i810 drivers, but there's no difference.

I don't understand why the X server appears to be completely disregarding the resolution settings specified in xorg.conf. Is there a way to absolutely force it to run at a specified resolution? Any other ideas?

Thanks a lot for any help.

xorg.conf:

# Xorg configuration created by system-config-display

Section "ServerLayout"
	Identifier     "single head configuration"
	Screen      0  "Screen0" 0 0
	InputDevice    "Keyboard0" "CoreKeyboard"
	InputDevice    "Synaptics" "CorePointer"
EndSection

Section "InputDevice"
	Identifier  "Keyboard0"
	Driver      "kbd"
	Option	    "XkbModel" "pc105"
	Option	    "XkbLayout" "us"
	Option	    "XkbVariant" "intl"
EndSection

Section "InputDevice"
	Identifier  "Synaptics"
	Driver      "synaptics"
	Option	    "Device" "/dev/input/mice"
	Option	    "Protocol" "auto-dev"
	Option	    "Emulate3Buttons" "yes"
EndSection

Section "Monitor"

 ### Comment all HorizSync and VertSync values to use DDC:
 ### Comment all HorizSync and VertSync values to use DDC:
 ### Comment all HorizSync and VertSync values to use DDC:
 ### Comment all HorizSync and VertSync values to use DDC:
 ### Comment all HorizSync and VertSync values to use DDC:
	#HorizSync    31.5 - 90.0
	#VertRefresh  59.0 - 75.0
	Identifier   "Monitor0"
	ModelName    "Dell 1280x1024 Laptop Display Panel"
	Option	    "dpms"
EndSection

Section "Device"
	Identifier  "Videocard0"
	Driver      "i810"
EndSection

Section "Screen"
	Identifier "Screen0"
	Device     "Videocard0"
	Monitor    "Monitor0"
	DefaultDepth     24
	SubSection "Display"
		Viewport   0 0
		Depth     24
		Modes    "1400x1050" "1280x1024" "1280x960" "1280x800" "1152x864" "1024x768" "800x600" "640x480"
	EndSubSection
EndSection

[lmo]

Some guesswork
These commands are typed on the command line
xdpyinfo | grep dimensions
xdpyinfo | grep resolution
xrdb -q

There may be a range of posibilities from 0,1,... for -s in the folowing experiments
xrandr -s 0
xrandr -s 1
...
xrandr -s 5
and so on

Some of them will work and some of them will be horrible mess.

In /etc/X11/xorg.conf,
Section "Monitor"
can have an entry
DisplaySize width height
where width and height are milimeters measured with a ruler.

In recent xorg, this may change some numbers in the above commands, but for me, the net effect was: no net effect

[hilbert24]

I got my correct resolution by doing the following (in order)-

1. Install 915resolution.
2. Run 915resolution
915resolution <mode> <width> <height> [<bits-per-pixel>]
3. Administration > Display. Configure to desired resolution.
4. Relogin to get X restarted.
5. Preferences > Screen resolution. My desired resolution shows here. Choose it. It works!

If this works for you, you may want to put 915resolution in one of your startup scripts that get executed before X is started, e.g. /etc/rc.local

Hilbert

[pytheas22]

Thanks, Hilbert and Imo. I tried following these directions and a lot more but it just doesn't work. I'm thinking that maybe there's a bug or something else weird going on with my computer. Neither of you happen to be using Dell Inspiron 1150's with i855 graphics chips, do you?

I used to have a weird problem where the mouse cursor would disappear (but the mouse remained completely usable) after ctrl-alt-f[1-6]ing out of X and back in. They fixed that in X11 a couple months ago, but maybe my inability to change screen resolution even using the 915resolution program is a similar bug. That's all I can think of.

Thanks again for the help.

[newfc2user]

Pytheas,

Are you sure that Windows had the resolution at 1280x1024 on that machine? The reason I ask is that I have a Dell Latitude D400 which has FC6 loaded. Initially I thought I had the same problem that my resolution would not be higher than 1024x768. But another D400 running Windows seemed to have better resolution that looked like 1280x1024.
Turned out the Windows machine was really 1024x768 only but the fonts and icons on the machine were smaller. FC6 stock has larger fonts and icons. I was able to go into Gnome prefs and make the adjustments so now my laptop seems to have the same resolution as the Windows machine.

[lmo]

The
#HorizSync 31.5 - 90.0
#VertRefresh 59.0 - 75.0
if not commented out may have an impact on the display, but they must be valid for the particular monitor being used.
I am using
HorizSync 31.0 - 80.0
VertRefresh 60.0 - 75.0
which I read on the monitor's box.
It's a flat panel Proview PL916s2 and doesn't have the same capabilities as a Viewsonic picture tube monitor that burned out.
The X setup programs are not very good at guessing these values sometimes, but leaving them commented out works better than using out-of range values.

In the Settings-->Display Settings or Monitor Resolution options, choosing a different hz changes the way the display is centered or off-center. Some of this stuff just works by magic sometimes.

There is a whole range of settings to spend a lot of time messing with documented in
man xorg.conf

There is also xvidtune which used to work on the old "picture tube" monitor, but it doesn't work on the new flat panel. It used to be that messing with xvidtune and modelines could change the display a lot.

[polyman]

Are you sure your Laptop screen can handle 24-bit color resolution? I had a similar problem with my laptop trying to get a screen resolutin of 1440x900.



Under Linux: (Note: you will need ‘root’ access)

1) First select a Monitor from the Display Settings that will encompass the resolution that you are looking for. In my case, I choose a “Gateway VX900’ under….

“Applications-->System Settings-->Display-->Hardware”

Note: the obvious choice, "Generic LCD screen" does not work with my laptop.



2) Select the resolution 1600x1200 this will encompass the resolution that I want … 1440x900

“Applications-->System Settings-->Display-->Settings-->Resolution”


3) Reboot



4) Restart Linux and open a terminal with ‘root’ access to that terminal



5) Change into the directory containing the Display information…

cd /etc/X11


6) In the terminal window type… (or what ever resolution is applicable)

gtf 1440 900 60


Note: 1440 = X dimention
900 = Y dimention
60 = refresh rate

…and note the information displayed for Modeline


7) make a backup of your ‘xorg.conf’ file just in case... i.e.

cp xorg.conf xorg_backup.conf


8) open an editor such as ‘gedit’ and look at the file called ‘xorg.conf’ i.e.

gedit xorg.conf



9) scroll down within the file until you find the section labeled “Monitor”. Locate and change the Modeline value to read what was reported from Step #6. Note you can comment out what is already there by placing a # sign at the beginning of the line.


9) scroll further down until you find the section labeled “Screen”… Here you will add another display SubSection that looks like this…

SubSection “Display”
Depth 18
Modes “1440x900_60.00”
Viewport 0 0
EndSubSection


Note: the 'Modes' line should contain the same name in quotes as obtained from Step #6


10) Save the file and Reboot Linux


11) Go to the “Screen Resolution” setting under “Applications à Preferences à Screen Resolution” and change your setting to 1440x900. Follow the prompts and you should be in business.