ATT RG Unit

DIRECTV-no-help-at-all said:

we want to help clear things up. 

That would be a welcome change.

Coax cables are required for RG units when it is used for DIRECTV Satellite service.

The OP was talking about his Residential Gateway, the AT&T device that connects his home to the Internet.  Whether or not he has DIRECTV Satellite service has no bearing whatsoever on whether or not he should or should not have coax on his RG.

In the case, for DIRECTV Stream, it would be necessary the power cable and the HDMI cable. It does not require a coax connection.

RGs do not have anywhere to attach an HDMI cable.

@dflowers asked:

When I had ATTUverse the RG had a coax cable connected to the "cable" male connector on the back of the RG.  When I switched to DirecTV Streaming every connection on the RG essentially stayed the same.  My question is, do I still need a coax cable connection to the RG?

The answer is that it depends on how your RG was connected to the network when you were first installed.  If the coax was only there for connecting your U-verse TV receivers, then you no longer need that connection.  If the coax was also used for your run from the NID to the RG, then you would still need it. 

So... is there a cable in either the Green port or the Red port on your RG.  If so, then that's how your RG connects to the AT&T Network, and you no longer need the coax connection.  If the Red and Green ports are both empty, then you need to leave the coax connection.