Unknown monitor, intel driver, want to set VGA resolution to widescreen TV

Question

I have a Sony Bravia LCD television, which is now plugged into my laptop using a VGA cable.

I am running an HP Compaq laptop, with a video driver of:

00:02.0 VGA compatible controller: Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller (rev 03)

In earlier versions of Ubuntu, it was nearly at the right resolution; in a brand new installation of Ubuntu 11.04, however, it has reverted to a maximum of 1024x768.

Trying to set the resolution using xrandr is giving me annoying error messages, and I read conflicting information about the latest version of Ubuntu not using xorg.conf to set my resolution: is that right?

I'd be grateful for a little bit of help here: in either convincing Ubuntu to recognise the monitor, or to force Ubuntu to change the resolution. Since I'm running this as an external monitor, and the internal LCD screen works perfectly, I'm concerned about breaking the internal LCD support with display reconfiguration as well.

Solution 1

From a Google+ discussion from Dean Wallace:

xrandr -q gives you list of modes and displays. The Sony is connected to VGA1 on my setup.

cvt 1360 768 outputs this

# 1360x768 59.80 Hz (CVT) hsync: 47.72 kHz; pclk: 84.75 MHz
Modeline "1360x768_60.00"   84.75  1360 1432 1568 1776  768 771 781 798 -hsync +vsync

copy everything AFTER Modeline and paste to xrandr:

xrandr --newmode "1360x768_60.00"   84.75  1360 1432 1568 1776  768 771 781 798 -hsync +vsync
xrandr --addmode VGA1 1360x768_60.00
xrandr --output VGA1 --mode 1360x768_60.00

now that should adjust your resolution, look in the monitors applet in system prefs, should be there, set it and apply... if it doesnt keep after a reboot then add the commands to .xprofile in your home folder. so add

xrandr --newmode "1360x768_60.00"   84.75  1360 1432 1568 1776  768 771 781 798 -hsync +vsync
xrandr --addmode VGA1 1360x768_60.00
xrandr --output VGA1 --mode 1360x768_60.00

save/quit/reboot

(I have yet to save these for a reboot)

Solution 2

I don't use multiple monitors, so I can't answer that part of your question. But maybe I can clarify the logic behind the xorg.conf configuration file.

From man xorg.conf:

Xorg supports several mechanisms for supplying/obtaining configuration and run-time parameters:

• command line options
• environment variables
• the xorg.conf and xorg.conf.d configuration files
• auto-detection
• fallback defaults.

When the same information is supplied in more than one way, the highest precedence mechanism is used. The list of mechanisms is ordered from highest precedence to lowest. Note that not all parameters can be supplied via all methods.

The X server is thus able to automatically detect the connected hardware. As far as I know this is the case for some time. If the auto-detection fails you can do the configuration manually, by creating a configuration file. There are several locations where you can store the configuration file. The locations are listed in the man page of xorg.conf. The default location on Ubuntu is /etc/X11/xorg.conf. If you create a configuration file, then you don't have to configure everything manually. Instead you must only configure the parts where the automatic detection fails.

Comments

[Anny Igi]

Are you using a HDMI cord? With my TV (it's a Bravia too) only the HDMI will support the correct resolution. The "PC" port doesn't seem to work correctly at all. By "the latest Ubuntu" you meant 11.04, right?

[jamescridland]

I've clarified the original question (but yes, 11.04). The TV does support the correct resolution (I've upgraded from a Mac) via VGA.

[Wilf]

Relevant, this question: How can I make xrandr customization permanent? - the answer here can be used to have the display configured whist lightdm loads so it display correctly.

[jamescridland]

Am I correct, however, in thinking that Unity doesn't actually use the xorg.conf file whatsoever? Some of the reading I've done suggests that: which makes the wiki entry, that suggests changing xorg.conf, rather less than useful for those of us on Unity.

[Gabor]

xrandr --newmode .... lines gives me an Error of failed request: BadName (named color or font does not exist)