I do! Well it is through a comcast cable box, but it should be similar. I do have the advantae also of having the high definition box which allows me to use the component connections. If you have the box, just check the back for which outputs it has and make sure the Dell monitor you want has the right inputs. As long as the box allows you to output with something other than coax, the monitor should have the input.
The other thing you need to consider is audio. You need to make sure whatever setup you have can accept the audio (and that the box outputs audio on a separate line, which is really only a problem if the box only outputs with coax.)
If you have any more specific questions, let me know.