@kd5312, I just felt the bottom of my 4800 and I'd say it's pretty warm, normal, and not a problem. You might want to try enabling "Power saving" under Settings->System->Power if your Ultra (there are several "Ultra" models; a model number is always better) has that option. In my experience it doesn't save much power and often causes more trouble than it's worth. I'm not using "power saving" and I use the aquarium screensaver which I'm sure uses a significant amount of processing power and contributes to the heat.
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