No, it wouldn't run any cooler. My 663 gets pretty warm to, and right now I only have a composite video out to my little tv until I can get a new flat panel. It must just be a warm running receiver. I don't think the video processing really generates the heat, it's the amps that do that. No sense in running HDMI to your tv, since you would then only be able to get standard dolby digital and dts, as toslink and spdif don't have the bandwidth for dolby digital + and TrueHD.