Pontypridd are also in the Cup semi-finals, but only after repelling a gutsy display from underdogs Builth Wells to win 28-20 at Sardis Road.
Scrum-half Adam Powell and wing Chris Clayton looked to have Ponty cruising to victory with tries in the first half, but ASDA League One strugglers Builth, in the last eight for the first time in their history, fought back to level the scores early in the second half. Full-back George
Jenkins and then skipper Wayne Morris went over either side of halftime to stun the 2002 Cup winners.
Ponty, led by club talisman Dale "The Chief" McIntosh, responded in emphatic style. Prop Scott Roberts crashed over 12 minutes from time before fly-half David Flanagan added the conversion and a pair of penalties to put his side out of sight. Builth were determined to enjoy their day and grabbed a third try through No.8 Ben Duggan before the whistle.
Winger Elgan Jones scored the only try of the game as relegation-threatened Cardiff sneaked into the semi-finals. Fellow Principality Premiership strugglers Llandovery were chasing their first-ever Cup semi-final spot, but couldn't take advantage of the first-half wind at the Arms Park, with players from both sides limping their way to a 0-0 scoreline at halftime.
Cardiff Blues outside-half Nick Macleod finally gave the scorers something to do with a penalty goal in the 65th minute, and Jones clinched the victory with his seventh try of the season in the final minutes of a dreary game.
In the final last-eight match, Wales legend Jon Devereux rolled back the years to fire Maesteg into the semi-final. Devereux, who turned 40 last Thursday, scored two first-half tries at the Llynfi Road ground as his club kicked Newport out of the tournament. It was the dual international's first match of the season and the Black and Ambers had no answer to his power in the midfield.