Flicker and snowy effect aren't normal. First thing I would check is swap out the hdmi cable and see if its that. I don't know what else to try for that problem.
I can suggest something for ps3 settings that I've figured out after fiddling with tv/ps3 for a couple days. Set RGB full range to full on ps3, also go on the tv go to picture-advanced picture-hdmi/dvi rgb range and set whatever hdmi the ps3 is on to nonstandard. It makes games look better and increases the range of black to see blacker than black on blu ray.