LCD "scan line movement" effect

[nhelman]

This is more of a question about monitor technology than about MonitorTest, and hopefully some way to resolve what could be a problem.

I just purchased an LCD flat panel monitor, and being a proud owner of MonitorTest, I decided I should probably ensure the monitor is calibrated properly.

Upon starting the test, the top left circle of the very first screen startled me. It has the same sort of effect you get when videotaping a computer monitor, in which, I believe, scan lines on the two devices conflict with each other, only at a much more rapid rate.

It occurred to me that the refresh rate probably has something to do with this, so I went to my nVidia control panel and adjusted it from 60Mhz to 75Mhz. It appeared to slow the effect down somewhat, but not too terribly much. My guess is that I'd have to have a 200-500+ MHz refresh rate if that's the solution.

Any idea what's going on, and how I can resolve the issue. Short of that, this is a fabulous monitor, and MonitorTest proves it.

Thanks,
Neal

[David (PassMark)]

Most LCD monitors are designed to run at 60Hz. They do not require a high refresh rate like old CRT displays to have a stable display.

If you have a look at the manual that came with your LCD you'll probably find that it doesn't handle much more than 75Hz (and doesn't need to).

There should be no flicker / scan line movement at 60Hz on a LCD. Do not try running your LCD at higher refresh rates.

I would,

1/ Check that you see the same behaviour on another video card. Maybe take it around to your friends place for a test). It might be the video card at fault.

2/ Switch to using the DVI (Digitial) connection if your video card and LCD monitor have one. This should give a better picture than the traditonal analog connection.

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David
PassMark