How long have you had the PS3? Try using compressed air to dust out the vents. If you are technically handy you could open up the PS3 and clean out the insides as well. Is there a yellow light on the power indicator or is it still red? Can you eject games? Make sure all of the cords are inserted snugly. If you have it connected through HDMI the cable may have gone bad or even the HDMI connector on the television. You could try connecting it to a different HDMI port and see if the problem is still happening.