pc to tv problem

[sd69]

ok i,ve just connected my pc to my 42" plasma but my desktop is so out of focus that its unreadable,have tried tv settings but nothing.anything else i can do

i mainly got the lead to watch movie's as i d/l xvids upstairs then bring my pc down to watch movies and they play no problem also just tried the cables on my son's tv and he does'nt get anything.

s-video and sound lead to 3 jacks

[pepsik]

most cards have a dual display setting or an external tv setting that has to be turned via the video cards software.