Odd horizontal lines

I've been experiencing this for a few months now, but my monitor is displaying odd coloring... I would show a screenshot, but I've tested that by taking one and looking at it at college, and it doesn't the lines...

Above this entry box, for example, is a black banner ad from Leapfish. To the right of the add, and lined up top to bottom with it, is a yellowish bar. The color of this seems to depend on the color of whatever is casting this 'shadow'.

Is my monitor dying, or is there some setting somewhere that I can use that will stop this, or will I just need to get a new monitor? This one is a 6 year old 21" CRT that has seen a hell of a lot of use..


Knows where his towel is.
Staff member
Somewhere on your CRT should be a "menu" button (or similar) which will take you into some firmware routines for setting up the monitor (image width, height, skew, barrel distort, etc)
First thing to find and deploy, before you start fiddling with any other settings, is the "degauss" option.
This puts a big a/c surge through the CRT deflector coils, to remove any semi-permanent magnetic residues that gradually build up in a CRT monitor. (don't worry about the disconcertingly loud "clunk" - that's normal)
Hopefully, that should remove any colour ghosting or fringing.
This is something you should do every few months with a CRT, or whenever you move it to a new location (it will get a residual bias from the earth's magnetic field, which will change with location/orientation).

Only after a good degauss (or two or three if it's not been done for a while), should you attempt to use any colour gun alignment controls that might be provided in one of the menus.
If you start to play with any of the controls, make a note of all the settings before you start so that you can always get it back to where you started if you end up making it look worse.
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I have regularly degaussed the monitor since I received it... And doing so now has absolutely no effect on the display... I've just gone through all of the settings, and none of them seem to make the shadowing go away.. Changing the Input level from 0.7 to 1.0 actually made it more apparent...


Knows where his towel is.
Staff member
It sounds as if it's just suffering from a bit of old age then. Still, at least flat screen monitors have come down to about 1/10 of the price they were when you bought that CRT 6 years ago.
They're even going 3D for only about double that now.


Mostly Harmless
Staff member
I would suggest booting from a Linux Live CD and making sure you get the same results just to rule out any software/driver issues.


Super Moderator
Staff member
Have you tried resetting the monitor to factory default settings? Your CRT may be incapable of correctly handling the resolution you have it set on. Try a different resolution (800x600 for starters) and see if you get better results.
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I have reset the monitor to factory settings, and booted the monitor in an Ubuntu 9.04 insatllation as well as the live CD.. The lines are less visible with the factory settings, but they're still there, and were present when running from Ubuntu on my HDD and on my CD.