I bought a new Viewsonic VA903b to use with my G4 Mac Mini. I set it to use the display profile for this model, at 75 Hz, using a VGA cable with Apple's DVI adaptor. While generally the picture was good, characters seemed a little darker/heavier, and the last degree of sharpness seemed missing from the images, compared to my HP Pavilion LCD monitor. Also, when I first turned the unit on I saw a tiny but noticeable "data shimmer" on vertical edges, which seemed to settle down after 30 minutes or so but never entirely disappeared. I thought my new monitor was a lemon! Then I reset it to 60 Hz, and suddenly it looks fabuluous, with no vertical simmering, perfect sharpness, etc. So obviously, if it looks and behaves great now there's no need to return it. Still... What gives? i thought the rule of thumb was that 75 Hz was the way to go, and that a slower refresh rate such as 60 Hz was usually the cause of these kinds of problems -- not the solution to them! Does my computer, monitor, or cable live in Bizarro-land or something?