Green dots appears while watching a dvd on Viewsonic LCD screen

I'm having a ViewSonic 24” Full HD widescreen LCD. I had hooked up with my SD freeview box without any problems and the screen is working absolutely fine. Now the problem is that whenever i try to watch a dvd through my DVD player, i can see green dots on my ViewSonic LCD screen. But i can't any see any dots when i try to watch tv through Freeview box. If i try to use my scart lead rather than using a HD cable, i can not see any green dots, even if i try to view a DVD and the screen seems to be fine. Can any body tell me that what is the actual problem that i'm having while watching a dvd? Is it related to my tv or is with my HD cable? Kindly provide me the correct logical solution in order to resolve the above issue.

Try to make sure that your hardware acceleration is been not set as too high. You can check it out by going in to display properties --> settings tab--> Advanced--> and then select trouble shoot tab. If that doesn't work out for you then try to reinstall your display drivers.

Check out whether you the HD cable are inserted properly or not. Also make sure that there are no holes on the HD cable and it is connected properly on your SD freeview box. Also check out that the dvd is trying to play, is in proper condition or not. Sometimes scratches dvd may also cause you the green dots problem on your screen.

If you still face the above issue, then it is highly recommend that you contact your manufacturer for the above issue. He might be able to help you in order to resolve the above issue.