All I have seen are analog inputs for capture purposes. You could use a tuner with HD capability and spool the output to disk, but then you won't get the DirecTV tuning capability. If DirecTV has any channels that are unencrypted using QAM encoding, you could grab those with a card like the MDP-130, but I doubt they are using QAM, or that any of their channels are unencrypted.
In other words... application denied!
Oh, one thought, rather than look at TV Tuner cards (for which capture is, after all, an add-on), you might look at professional capture boards. Not sure this will be any more successful. I found a few just nosing around, all in the $200+ range, but most of them no longer offered for sale.