hi there, I have made a ticker in my software using Managed DirectX (Direct3d). one very unusual bug is producing in my software. when ever i run ticker Text (scrolling horizontally) i get a jerk after a specific time on PLASMA Screen but did not get the same jerk on LCD or monitor. I dont know how to handle it. is there any extra parameter of device i have to set specially for plasma or any thing else that can help me .... Please reply soon... Thanx

thanx for replying .....
but this jerks is coming on monitor, it is coming on Plasma Screen which is completely diffrent techonology than monitor or LCD.
i have checked the same scenario with different cards..

Hi Usman,
This sounds like a refresh problem. You can often get this with horizontal scrolling. For example, put a ticker onto a DVD video and it can play beautifully smoothly on a "TV", but look quite awful on a computer display. This is down to the refresh rate of the screen. Computer monitors for example typically run at around 60Hz. Try and display a bit of 25Hz PAL video in this environment and horizontal scrolling can look jerky - indeed it can effect any form of horizontal movement in certain circumstances. (The rule of thumb is that this looks at its worst when objects take around 3 seconds to cross from one side to the other.)

Now, this might be nothing to do with your plasma issue. What I would do is find out what the refresh rate of the screen is, and - if your application is specific to that screen - try and tune your DirectX refresh rate to match. You might find everything runs smoothly.

You can find problems by the way if you're running both a plasma AND a standard monitor (CRT or TFT) from the same PC at the same time with the same image (i.e. cloned view as opposed to dual screen). If you're doing this, the graphics card might well be locking to the frequency of the monitor.

Hope that helps...