question about scan (?) lines with dual computer monitor/HDTV set up

[(Conky)]

Hey all, a friend recommended this forum for all questions computer related, so here goes.

For a few years I've been using a Playstation 3 to use Netflix and stream video content from my computer. However, it seems to have become distractingly loud and the streaming has always been unreliable.

As an experiment, I purchased a long HDMI cable to connect my TV directly to my computer. It works great, but the somewhat minor problem I'm having is that if the computer is set to duplicate the images on both the monitor and the TV, I get these horizontally moving lines on the monitor when gaming or using a media player/tube site. Curiously, this effect goes away when I set the computer to extend the display across both screens.

My ultimate desire is to be able to do away with the minor hassle of switching the screen set up in the control panel every time I want to watch something on the TV. So does anyone know if there's some setting to make this possible? Does it have something to do with differing refresh rates between TVs and computer monitors perhaps?

Thanks for any help!

 

[sdifox]

set them up as dual display with different parameters. Chances are you are not running your monitor at 1920x1080@60Hz and that is causing an issue when you clone display.