strange monitor problem

[Prosthetic_mind]

ok, as some of you know, I got a new monitor a while back, and it's generally been peachy. However, something quite odd has been manifesting itself in the last several weeks, and I figured it would be wise to see if anyone else has had experience with it-

my monitor is a Dell Trinitron (computer registering it as a P1110),
and for some reason, most often within 5 minutes of starting the computer, and most likely when the brightness is turned up, the screen will decide to change dimensions. The edges of the screen will quickly move beyond the edges of the monitor's display, but only when I do something that significantly changes the colors shown on the screen (like fullscreening a window from the desktop), and will move back to their original position when the previous colors are restored (minimizing said window). My guess is that the auto adjusting system is damaged or defective in some way (it doesn't actually optimize the screen very well when activated, setting the alignment improperly and setting the size to smaller than the screen). Any help is appreciated, this really isn't affecting me yet, but it'd be nice to know if it's a precursor of things to come.

[ski]

If you have not already done this, then see if the problem happens with the auto-adjustment feature disabled.
If you've tried that, then the monitor may be failing. If possible, see if the same problem happens with it connected to another system, or if the problem stops with a different monitor connected to your system. If yes for either one, then yours is bad.

[Prosthetic_mind]

How exactly do I turn off, or for that matter, turn on auto adjust? To my knowledge the auto adjust is simply a button on the monitor that sets the screen to some factory default or something. Honestly, it's only happened to me twice, but I was curious whether it was a common problem or something odd, because I haven't seen monitors do that before.

[ski]

Press the monitor's Reset button when the problem happens.
If that does not work, then press the monitor's Menu button, select "Size/Center" from the menu, and you should be able to adjust the horizontal and vertical picture size and centering, and enlarge or reduce the picture.

I know that even if either one of the above suggestions works, they are just band-aid solutions which can become tiresome very quickly.
However, other than a failing monitor, the only other thing that may be causing the problem is a changing resolution.
That can be checked by doing the following:
Check the current settings for your video card's resolution(Ex.-1280x1024) and refresh rate(Also called vertical frequency, Ex.- 85 Hz).
When the screen size is normal, press the Menu button on the monitor, and check if the vertical frequency and the resolution shown on the monitor's display match your video card's settings. If you do not have the monitor's manual, then use the following link as a reference:
http://support.dell.com/support/edocs/monitors/p1110/En/controls.htm#GEOMETRY The vertical freq. is the 2nd value of the 9th item in the "On Screen Display (OSD) Menu System" section as noted in the above link. The resolution is the value in the 10th item in the same section(In order for the resolution to appear in the OSD Menu, it has to match one of the factory "Preset Display Modes" shown here -> http://support.dell.com/support/edocs/monitors/p1110/En/specs.htm#Preset )
When the problem occurs, press the Menu button again, and compare the the values for the vert. freq. and the resolution with the previous values. If they're different, then the vert. freq. and resolution settings may be automatically changing. Uninstalling and reinstalling the current video drivers, or installing updated drivers may fix things.

[SkyTrax]

i've seen that often on old televisions and monitors, i have asked for the same problem long time ago, the screen become bigger when light colors are displayed and become smaller when dark colors are displayed... On my CRT monitor, the change in dimension is about 1mm when i minimize and restore a windows, but i had an old Hitachi 1984 television that the change was about 1 inch, that was irritating, and the more the brightness is up, the more the change will be big....

this is only my experience, i don't know if it's your talking about...;)

[Prosthetic_mind]

that's exactly the problem. This is supposedly an old monitor, it's status when I bought it was "used", I don't know exactly how old, but it doesn't seem to expand or contract once it's been used for more than 20 or 30 minutes.