If you wish to change from HD to SD, when you take out your HDMI cable and replace it with the AV cable, it won't automatically reconfigure the video settings, and you'll get a blank screen. This video is a lengthy and detailed tutorial showing how you can reset your Playstation's video output settings from High Definition (HDMI) to Standard Definition (AV/SCART).

Watch and listen carefully. But in one sentence: When the PS3 is all set up for standard definition and on standby (red light), press AND HOLD FOR 5 SECONDS the ON button (touch sensitive on the old models) even after it's turned on, until the console bleeps twice.

Thanks for watching!