They temporarily opened a four-point lead and were helped back to the heady position they held for so long by leaders Glasgow, who surprisingly crashed 29-6 to the Scarlets.
After taking time to get going, it was Ulster who were spitting fire rather than their Welsh counterparts. They controlled the scrums where again Ricky Lutton did great work while the lineouts went like a dream.
Tries by Tommy Bowe, looking very sharp on his first start since returning from injury, the impressive Stuart Olding and the ever-alert Darren Cave helped Ulster to a comfortable half-time lead before Paul Marshall scooped up the bonus try.
Controlling things at fly-half, Ruan Pienaar was again the essence of consistency and class and recorded a 100 per cent kicking return with four conversions and a lone penalty.
However, it was hardly an auspicious start for Ulster, with Paul Marshal kicking directly into touch from the first play of the game. Then came a penalty from the line-out, but fortunately for the home side Tom Prydie’s attempt from straight in front skewed away to the left of the posts.
For the next five minutes, Ulster just couldn’t get their hands on the ball as the Dragons convincingly picked and drove their way upfield. However, twice the exciting Iain Henderson brilliantly galloped through midfield to finally awaken the fans from their slumber on a sunny, but cool evening.
It needed some real urgency to finally get the scoreboard moving halfway through the first half, and that was exactly what happened from an Ulster scrum on the Dragons’ 10-metre line. Number 8 Nick Williams picked-up and delicately fed Marshall who sprinted clear of the covering defence before sending Bowe over in the corner with Pienaar knocking over the touchline conversion.
Backchat from Dragons’ fly-half Dan Evans in the 27th minute not only saw him yellow carded by Welsh referee, but the extra 10 metre penalty advantage saw Pienaar stretch Ulster’s lead.
A brilliant diagonal run by Craig Gilroy almost set up Ulster’s second try soon after, but a lack of patience saw a golden chance evaporate. But Ulster had finally found that mojo that has been a long time coming, and the ever-improving inside centre Olding finished off a move started when Bowe entered the line down the left which caused all sorts of mayhem.
Next up was Olding’s midfield partner Cave, who took advantage of a poor piece of defending by Prydie, whose feeble attempt to clear a Peter Nelson grubbber on his own line only found Williams in midfield. He promptly moved the ball wide to Cave who licked his lips when he found himself among forwards and did the needful.
With Pienaar landing another conversion from out wide, Ulster went in at the break with a 17-point cushion.
Within four minutes of the restart, Ulster had the bonus point in the bag when Marshall nipped around the tiniest space on the blindside to score. Pienaar again did the needful.
Ulster did try to add to their collection, but the job was done and a home semi-final slot al but assured.
The Dragons did manage a breakaway try for their endeavours in the 69th minute with Prydie getting the final touchdown after good hands between backs and forwards.
Scorers for Ulster: Tries: Bowe, Olding, Cave, Marshall; Penalties: Pienaar; Cons: Pienaar 4
Dragons: Try: Prydie
ULSTER: P Nelson (O’Connor, 68); T Bowe (D’Arcy, 63), D Cave, S Olding (Allen, 52), C Gilroy; R Pienaar, P Marshall; T Court (Black, 50), R Best, capt (Herring, 65), R Lutton (Fitzpatrick, 58), I Henderson (Stevenson, 44), D Tuohy, R Diack (Birch, 65), M McComish, N Williams.
DRAGONS: T Prydie; W Harries (Jones, 40), P Leach, J Dixon (W Evans, 74), R Wardle (Tuilagi, 64); D Evans, J Evans; A Coundley (Williams, 55), S Parry Gustafson, 62), N Buck (Way, 55), A Coombs, capt (Jones, 68), R Sidoli (Jones, 60), D Lydiate, D Waters, T Faletau.
Referee: Leighton Hodges (WRU).