Want to plug PS3 into the PC and play it on monitor?

I want to play the PS3 on the monitor VIA PC. However, I only have one DVI port, and it's on the tower block itself. The other port is something else that connects the monitor to the tower block. Will I be able to do this VIA the tower block? I don't want to order a HDMI to DVI cable if it's not going to work that way.