I have a similar problem with my monitor that happens only at 1024x768 2d.. IT DOESNT HAPPEN IN 3D. so weird.
for example when i load counterstrike to join a server thats when it happens, as soon as i join the game everything is fine. weird i say
somethin inside my monitor aint workin so well me thinks.. ]
anyways it is like a earthquake goin on and my screen is "Wavy" like you say swaying left to right. I Just deal with it till i can afford a better one !
you get what you pay for is true for me... i bought this microscan 19" a long time ago 2+ years for like 300$ that was a bargain.