I have a newer PS3 slim 120 and recently while general use or gaming my screen will momentarily go black for a few seconds then comes back. This makes it extremely difficult to kill zombies. I have ruled out TV's and HDMI cables. I haven't messed with settings since I first set up the system many moons ago. Am I losing my HDMI port?
How have you rules out TVs and cables?
Have you tried performing the video settings reset?
Sometimes its just a handshake issue and resetting the video settings on the PS3 can get rid of this annoyance for the most part.