Hello Doug. The VIA EPIA 5000AG Fanless mini ITX runs at 533Mhz. I don't know if you can find a way to underclock it. Fanless VIA Eden 533MHz Processor, Up to 1GB PC133 Ram, Onboard VGA, Serial, 4xUSB v1.1, LAN 10/100, Parallel. Does not have TV out. -- Chris.