Well, then the next thing to do is check your HDMI cable and then your TV. Always check the TV last as it's the most expensive to replace. Change out your HDMI cable and then take your PS3 to a friends house with a HDTV and see if it's still messing up there.
If it is still messed up on another TV AFTER changing the HDMI cable and moving to another TV, then it's more than likely your PS3. If it doesn't mess up on another TV, then it's your TV!!
Other than that man, I don't know what to tell ya. If anything, go to the PS3 boards on playstation.com and search around for your problem.