I installed Mythbuntu 8.04 on an A64 3500 box with 1GB and 7100GS, described in other threads.

I installed the current Nvidia proprietary driver via EnvyNG, no issues. It automagically set the desktop to 1920x1200 over analog VGA to match the 24" LCD I set the machine up with initially.

However, I gave the machine to a friend,who plugged in an old 17" CRT monitor before powering up.

The Mythbuntu desktop (Xfce) came up at 640x480 instead of something more reasonable like 1024x768. He shut down and plugged in a 17" LCD, and the desktop is "stuck" at 640x480 with huge icons. He finds it difficult to reset the resolution, including through the nvidia-settings panel, which doesn't show any options higher than 640x480.

How do you force and lock a resolution, preferably before I shut down and give a new build to someone?

What's probably happening is the nvidia driver is failing to recognize valid modes, so you have to tell it to stop checking with something like this:
Option "ModeValidation" "NoDFPNativeResolutionCheck"
(that's for LCD, of course)
Then, you give it only one mode to choose from in the "Modes" line. You may need a Modeline, as well.

I, admittedly, used the "spaghetti method" to get mine working, just pretty much throwing stuff at it until it stuck.

Here it is again (http://www.avsforum.com/avs-vb/showpost.php?p=13842360&postcount=3)

Not to start another rant, but Nvidia and ATI are still dropping the ball with their drivers, which should control/manage the xorg.conf file properly for you, even after monitor, resolution or refresh rate changes. This is 2008, not 1998, and simply plugging in a different monitor shouldn't jack up the screen resolution to the point of being unrecoverable without manual xorg.conf editing. :(

Whatever happened o the "Bulletproof X" initiative? The video driver control panel applet should be all we need to change resolution/refresh rate, and make it stick.

I hear you loud and clear, but it always comes down to simplicity and control: one must always be sacrificed in order to attain the other.

----------------
Now playing: Curve - Fait Accompli (http://www.foxytunes.com/artist/curve/track/fait+accompli)
via FoxyTunes (http://www.foxytunes.com/signatunes/)

To followup on this issue-

The coworker brought his machine back to my house. I plugged it into the Acer 24" LCD Mythbuntu 8.04 was installed with, and voila- the desktop booted to 1920x1200 automagically. At least we were back to where we started without intervention- plus one for Nvidia and Linux.

The Nvidia driver just didn't like the old tube CRT monitor, I guess, but Nvidia ought to handle resolution detection better and/or offer better failsafe options. Don't know why the Dell 15" LCD didn't "fix" the resolution detection after the CRT, but it was an older LCD, too.

Anywho, I simply launched the Nvidia control panel, sudo nvidia-settings, to change the resolution to 1024x768 @ 60hz for the target 15" LCD he planned to use, saved the xorg config in the applet, and shutdown. Before doing the Nvidia panel, I backed up the current "working" /etc/X11/xorg.conf, i.e.

cd /etc/X11
sudo cp xorg.conf xorg.bak

I also added mythmaster's option line to xorg.conf

Option "ModeValidation" "NoDFPNativeResolutionCheck"

before launching nvidia-settings. The new line was preserved by the Nvidia control panel when it wrote a new xorg.conf, in addition to a lot of other changes.

After plugging in his 15" Dell LCD, the desktop came up fine at 1024x768, and the Nvidia control panel reported the correct monitor model.

it's all good ;)

Moral of the story- don't plug in old monitors with bad/incorrect/missing DDC/EDID information on your Linux boxen...

http://en.wikipedia.org/wiki/Display_Data_Channel

http://en.wikipedia.org/wiki/EDID

The second Moral of the Story-

If you do a new Linux build with a monitor other than what you plan to use in service, it might be a good idea to do the procedure above before shutting down and moving the machine to it's final location and target display, i.e.

Backup the current /etc/X11/xorg.conf file
Add the line

Option "ModeValidation" "NoDFPNativeResolutionCheck"

Launch the ATI or Nvidia control panel from a term window as root (sudo).
Set the resolution and refresh rate to the target display.
Save the xorg.conf in the control panel
Quit and shutdown.
Move the machine to new location and connect target display.

I have an old LCD that doesn't properly report EDID and I used to have to change to "Generic LCD" in the control panel in order to get it to show all the possible resolution settings. I can't recall if there is a "Generic CRT" setting and I can't recall if it was only available in the KDE control panels or if it was also in the Gnome controls. :(

I wonder if hooking up the 24" LCD as the primary display and the CRT as secondary display in dual-head mode would make it easier to set up the CRT?

At least that way you'd have a working primary display so it might save you some rebooting.

BTW, this is one of the reasons I load the kubuntu-desktop package into my installs. The KDE monitor config panels have a lot more features and make it a lot easier to deal with these types of problems. Unfortunately, it would probably be a bad idea to do that with a Myth install.


Ooops look like you cross-posted while I was composing this. Well at least you got it working again. It would be nice if X had a wizard that would walk people through some of these common scenarios.

BTW, this is one of the reasons I load the kubuntu-desktop package into my installs. The KDE monitor config panels have a lot more features and make it a lot easier to deal with these types of problems. Unfortunately, it would probably be a bad idea to do that with a Myth install.

.

Good call, but unfortuantely, the Xfce desktop used in Mythbuntu doesn't have the Gnome or KDE resolution-setting control panels, or as full featured, at least.

But it appears the Nvidia panel was sufficient to resolve the issue, per my last post.

...BTW, this is one of the reasons I load the kubuntu-desktop package into my installs. The KDE monitor config panels have a lot more features and make it a lot easier to deal with these types of problems. Unfortunately, it would probably be a bad idea to do that with a Myth install.

Why would you think that? I hate the XFCE desktop and dislike Gnome, so I always install the KDE desktop in all of my Linux installs. This includes the MythTV boxes. There is no reason that KDE cannot be used.

Why would you think that? I hate the XFCE desktop and dislike Gnome, so I always install the KDE desktop in all of my Linux installs. This includes the MythTV boxes. There is no reason that KDE cannot be used.

I stand corrected. It just seems to me that a lot of people who choose to use a Mythbuntu distro do so because they want to know that everything in the install plays nicely with everything else. But when you install the zillions of packages that make up the kubuntu-desktop meta package you can throw that idea out the window. I thought that most people who prefer unusual distro/desktop manager combos would just install their favorite distro and then install myth in it instead of using a pre-canned myth distro.

KDE is not an "unusual" desktop. It is very common, and used and loved by many.

This is a quote from the main page of the Mythbuntu web site:
Unlike similar projects, Mythbuntu keeps close ties with Ubuntu and all development is given back to Ubuntu. This architecture allows simple conversions from a standard desktop to a Mythbuntu machine and vice versa.

...If at any time a user wants to, they can install ubuntu-desktop, kubuntu-desktop, or xubuntu-desktop and add a full desktop onto their installation.I encourage everyone to install the KDE desktop!

You have a problem with taking things WAY too literally.

Sorry Mac, I just saw some misstatements and felt they needed correcting. There are many newbies who look to this forum for advice. I don't want them to start out with info that is not totally correct.

You have contributed a lot to this forum, so keep it up!

I encourage everyone to install the KDE desktop!

Good reminder- while I like the minimalist simplicity and lack of bloat of Xfce, I've been wanting to give more recent KDE's a try.

I'd thought that Mythbuntu's Control Center only allowed the xubuntu desktop as a pick, but it actually has ubuntu (gnome) and kubuntu (KDE) desktops as picks, too.

Yes, you could get kubuntu-desktop in Synaptic, but I don't know if Mythbuntu has special settings it makes and/or preserves when installing kubuntu-desktop from its Control Center.