You would need another HDMI cable. One to go from the PS3 to the receiver, and one from the receiver to your TV.
You can get great cheap HDMI cables from www.monoprice.com
I have a Sony 720 reciever with four HDMI slots. I have one HDMI cable that I use with my PS3 to my TV. Now if I run that HDMI through the receiver do I need to get another HDMI to connect the reciever and the TV? could you guys help plz.