Leinster leapfrog Newport into fourth on the PRO12 ladder after convincingly dispatching the Welsh side 37-13.
Momentum swung between the two sides in the first half, as the teams traded penalties in the early minutes before Sarel Pretorious found the first try of the match.
Isa Nacewa managed to get Leinster back into the tie though, scoring two tries of his own to give the home team a 20-10 lead at the half's end.
The only scores for the majority of the second half came through a shot at goal for both teams, until Gary Ringrose and Cathal Marsh ran home two successive tries to secure the win for Leinster 37-13.
The hosts were out for revenge after a 25-22 loss to the Dragons last season effectively ended Leinster's chances at a play-off place.
Leinster's scrum forced a penalty out of the visitors and McFadden opened the scoring from the tee.
Newport drew level moments later through Tovey, but a high tackle from the Welsh side handed the lead back to Leinster with McFadden kicking two from two.
The Dragons threw their forwards at the home team and eventually managed to squeeze their way over for a try after 22 minutes. Pretorious got the try and Tovey slotted the conversion to give Newport a 6-10 lead.
The lead changed hands again when a speculative pass out to the wing found Nacewa in space, McFadden slotted the conversion to put Leinster 13-10 in front.
A line break from Ben Te'o lead to Nacewa's second try of the match. Nacewa converted his own try with McFadden sitting in the blood bin to give Leinster a 20-10 lead going into half time.
The sides traded penalties again in a relatively quiet second half to edge the scores up to 23-13. Just as the Dragons looked like they were getting a foothold in the game with 10 minutes remaining Leinster ran home two back to back tries.
Ringrose and Marsh scored within four minutes of each other to seal the win for Leinster 37-13.
Tries: Nacewa 2, Ringrose, Marsh
Cons: Nacewa, McFadden 3
Pens: McFadden 3
Pens: Tovey 2
Leinster: 15 Isa Nacewa (c), 14 Fergus McFadden, 13 Ben Te'o, 12 Noel Reid, 11 Garry Ringrose, 10 Cathal Marsh, 9 Isaac Boss, 8 Jack Conan, 7 Josh van der Flier, 6 Dominic Ryan, 5 Mike McCarthy, 4 Ross Molony, 3 Marty Moore, 2 Aaron Dundon, 1 Michael Bent
Replacements: 16 James Tracy, 17 Peter Dooley, 18 Jamie Hagan, 19 Rhys Ruddock, 20 Dan Leavy, 21 Luke McGrath, 22 Ross Byrne, 23 Cian Kelleher
Newport Gwent Dragons: 15 Carl Meyer, 14 Ashton Hewitt, 13 Ross Wardle, 12 Adam Warren, 11 Tom Prydie, 10 Jason Tovey, 9 Sarel Pretorius, 8 Ed Jackson, 7 James Benjamin, 6 James Thomas, 5 Rynard Landman (c), 4 Nick Crosswell, 3 Brok Harris, 2 Hugh Gustafson, 1 Boris Stankovich
Replacements: 16 Rhys Buckley, 17 Phil Price, 18 Shaun Knight, 19 Matthew Screech, 20 Nic Cudd, 21 Luc Jones, 22 Angus O’Brien, 23 Aled Brew
Referee: Ian Davies (Wales)
Assistant Referees: Eddie Hogan-O'Connell (Ireland), Shane Kierans (Ireland)
TMO: Jude Quinn (Ireland)