Idk....last time I was looking into this, I was trying to connect a PS3 to an iMac. You needed some expensive box converter like what Kanex makes. That was a while ago though.
That cable will probably work for the Dell but you might not want it for your TV. This is because that Monoprice cable does not support audio (look at its description). I am assuming you don't care about audio to the Dell but for TV, unless you are willing to pass the audio separately, you won't get audio on your TV.
Ideally you want a mDP-to-HDMI that does pass audio. There are plenty to be had and none are too expensive. Do a google search. Personally I have Inland adapter I got at at Fry's. Works fine if I connect the TV.