The side input is probably composite (yellow, red, white) or s-video, right? If so, you won't be able to get HD from those connections. You'll need to connect it to an HDMI input. YPbPr is component video (red, green, blue), which can do HD, but most devices wont send an HD signal over that connection. The major advantage to that connection is progressive scan (480p) and improved color fidelity. HDMI is better.