Easiest test is to hook up another monitor, if the problem still exists you swap out the vid card..
Ok, here is what happned: about two weeks ago strange shadows started showing up on my screen, sometimes they got brighter and easy to see, sometimes they are hard to see.
The shadows are seen next to high contrast icons, texts and pictures.
I searched google but found nothing lke this problem.
Allso i had the same problem half a year ago, and it fixed itself somehow. I think that this is a graphics card problem, because monitor menu (you know, where you adjust contrast, brightness...) does not have any shadows.
I have 17.5" Viewsonic monitor, Nvidia Geforce 9500 GT graphics card.

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