[Joey Joe joe]

Hey guys
I was wondering if any of you could help, I recently upgraded my graphics card without really researching how well it would work with linux.
I installed a radeon HD5450 and I'm now finding that when watching movies i'm getting 2 horizontal lines every now and again and some videos lag a little when changing scenes.
I'm using the propriety ati drivers but wondered if anyone could help shed some light

thanks guys