Monitor problem

[[AK]The Beast]

OK, so I snagged a used 21" HP P1100 monitor (built in 1997; HP model code D2846A), hooked it up, and discovered that when the vertical screen size is set above 35, a "fishbowl" effect sets in, where the middle portion of the screen appears rounded and magnified in the middle. As the vertical size increases, so does the visible size of the fishbowled area (though the same part of the screen remains in the fishbowl throughout). I've tweaked every setting I can think of (including resolution, both up to 1280x1024 and down to 800x600, and resolution, every setting available between 60 and the max of 85) but no luck. I also played with the monitor's control panel, nothing. I downloaded a manual for it, but it doesn't have any helpful information. Resetting to factory defaults doesn't fix it, nor does using the "autosize" feature. Any idea what sort of hardware failure inside the monitor could cause that problem? I REALLY don't want to have to put the 17" Trinitron back up--sure it's a nice monitor, but Secret Weapons looked so friggin' cool on Big Bertha here.

[[AK]Bribo]

What video card and operating system are you using?

[[AK]The Beast]

Radeon 9500 Pro under Windows XP. It's worth noting that when the screen "fishbowls", the monitor's onscreen control panel suffers the effects as well.

[Slaughter]

Have one of those nifty buttons on the monitor that fix problems?

you know, kinda makes the monitor flash and stuff..

I just got up so this probably isn't making any sense at all.

[[AK]The Beast]

If you mean degauss, yep, I tried that too--no luck.

[[AK]Bribo]

Does this fishbowl effect happen all the time or just under certain conditions?

[[AK]The Beast]

It happens any time the monitor's vertical size is set above 35. Horizontal size doesn't matter, nor do resolution or refresh rate.