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Resolution problems when using VGA splitter between Desktop and TV

So I bought a VGA splitter and a long VGA cord so I could send the output to my new HD TV. It worked fine, I had my screen duplicated perfectly onto my tv. That is until I restarted the computer. Now everything is screwed up.

When I unplugged the TV and restarted it went back to detecting my monitor and it worked like before.

When I have both the TV and monitor plugged in, I can't get better than 800x600 resolution. I tried playing around with xrandr and followed a blog substituting my own resolution numbers in to create a 1680x1050 mode display... well one of the numbers (or more) must have been wrong because everything is just a little blurry and looking at the screen was starting to hurt my eyes.

So I unplugged the TV and restarted... and here I am looking for some help. If I plug in the tv right now, all is well. Then if i restart and leave the tv plugged in, my resolution goes to hell.
How do I stop it from auto detecting and changing my screen resolution?
I don't have a xorg.conf file, from what I've read Ubuntu 10.04 and up no longer uses one, so lets not go there if we don't have to.

What is the resolution of your TV?

Quote:

Originally Posted by MTK358 (Post 4324750)

What is the resolution of your TV?

I'm actually not sure... its 1080p. I don't think that matters. When I had the tv running off the split signal the tv auto adjusted and it looked just fine. I'm not using it as a monitor per se, I'm using it to watch shows off of services like hulu.

1080p means 1920x1080.

http://upload.wikimedia.org/wikipedi..._scan_hdtv.svg

I thought that maybe your TV's resolution was much smaller than the monitor, and that that might cause issues.

workaround but not solved

I figured out a workaround that will do for now, but I will not mark the thread as solved until a more permanent solution is found. Here is what I did:

I booted the computer with the TV disconnected, used the command

Code:

xrandr --verbose

to get my current screen's settings.
Using those settings I created a script:

Code:

xrandr --newmode "MonitorAndTV" 146.2 1680 1784 1960 2240 1050 1053 1059 1089 -HSync -VSync

xrandr --addmode VGA1 "MonitorAndTV"

xrandr --output VGA1 --mode "MonitorAndTV"

and put it into my startup programs.

This of course is not ideal, my login screen is still in 800x600 resolution, if i create another user i would also have to duplicate the script and put it into their start ups... I would just like to unplug the TV, have it auto figure out the resolution then make that the default, and don't let it auto adjust again.

I found out how to make the script persistent. I followed these instructions from Ubuntu Wiki

Quote:

Setting xrandr commands in kdm/gdm startup scripts

Both KDM and GDM have startup scripts that are executed when X is initiated. For GDM, these are in /etc/gdm/ , while for KDM this is done at /etc/kde4/kdm/Xsetup. In either case, you can paste in an xrandr command line string into one of these scripts. For GDM, try putting them right before initctl -q emit login-session-start DISPLAY_MANAGER=gdm in /etc/gdm/Init/Default

Everything looks nice now. Hope this helps others.

Not sure if this will work for GNOME/KDE users, but here's the solution if you use startx:

Just enter the commands you want to run as X is started into ~/.xinitrc. It's basically a bash script that's run right after X is started.