Wingers Tom James (2) and Jamie Roberts shared out Cardiff’s tries at Murrayfield on Friday as the Welsh region ended Edinburgh’s hopes of staying in the Magners League title race.
It was fourth plays fifth at Murrayfield but there was clear distance between the teams at the finish as Edinburgh put in a forgettable display.
Little went right for the Scots, who had lost just one of their last seven games in the league.
A high error count and a 15-0 deficit left them chasing the game at half-time, while referee Alan Lewis kept them on their toes.
Coach Andy Robinson did empty his replacements bench in the second period but it mattered little as his players erred within sight of the try line and Phil Godman missed his only penalty attempt in the 38th-minute.
Edinburgh were gunning for their first league double over the Blues since the 2004/05 season but the Welsh region, 11-10 losers when the sides met at the Arms Park in January, were clearly clued up for this encounter.
They also got fly-half Nicky Robinson on for the final quarter as he made his long-awaited comeback from a thigh injury and is now in with a chance of playing against Toulouse next weekend.
Cardiff, who lost badly to Llanelli seven days ago, slugged it out in an opening quarter during which the home side held the edge but they failed to trouble the scoreboard.
Instead, the Blues were 15-0 up by the 31st-minute as after an initial penalty from full-back Ben Blair, both Tom James and Jamie Roberts crossed for a try apiece in a seven-minute spell.
The Blues, with Xavier Rush getting through an amount of work, built through the phases before the space was created for James to finish and allow Blair to convert.
Edinburgh’s defence then caved in to allow Roberts tag on his try. With Hugo Southwell putting in a poor tackle and Ben Cairns also left flailing, the powerful winger was able to surge over from 40 metres out.
Edinburgh had a purple patch at the start of the second half and they should really have scored.
But Simon Webster was stopped short of the line by a lively Tom Shanklin and John Houston was held up over the whitewash after a quick tap penalty from Mike Blair.
Robinson’s charges continued to press for the try and was almost rewarded when Godman’s delayed pass sent David Callam through a gap. However, the Edinburgh number 8 juggled and dropped the pass with the line at his mercy.
The result was effectively sealed in the 56th-minute when turnover ball allowed Cardiff get back within range. A fine incision into the attacking line from Blair paved the way for James’ second touchdown.
In front of a 2,395-strong crowd, the Blues then went in search of the bonus point try but a knock-on deprieved them of their best chance.
Edinburgh, 38-8 winners over Connacht last week, battled on but lacking their usual cohesion there was no late comeback from the below par Scots.