I'm told by Charter that there is no way to copy previously recorded shows from my dvr to an external hard drive. But my PC has an HDMI input, so it seems that the only issue might be determining the right codec to use.
Simple answer is no, this will not work.
Some people use the AverTV HD or Hauppauge HD capture devices and go through all kinds of hoops to capture from dvr's. It is not something I have tried. Take a look at this thread over at AVSforum: http://www.avsforum.com/avs-vb/showthread.php?t=1196020
That's probably an output.
At least computers with HDMI-Input exist:http://www.jolamedia.nl/product.php?productid=16187&cat=291&page=1