Substitute Federico Macheda went closest for the hosts before David Marshall tipped Alex Revell's header onto the crossbar to extend Rotherham's sorry run to eight league matches without a win.
They have not won away from home since they beat Millwall back in August and they hover two points above the relegation zone, as Cardiff slip down to ninth.
It was the Millers who looked most likely to pounce first at the Cardiff City Stadium.
Richard Smallwood caught Cardiff napping after some drab early action as his quickly taken free-kick found Welsh starlet Tom Lawrence deep in Bluebirds territory.
The on-loan Leicester midfielder found Scott Wooton who rounded Marshall but his touch was too heavy and Matthew Connolly cleared for a corner.
Cardiff are yet to go behind at home under Slade but they could well have done when a defensive lapse from the resulting corner led to a goal-line scramble, but Revell could not stab home.
It was Lawrence who provided some much-needed spark at the start of the second half.
He popped up on the left this time, in between the lines of defence and midfield, and glided past Sean Morrison and Ben Turner before fizzing a low shot at goal, but Marshall adjusted well to save with his legs.
The hosts could not find their rhythm and were on the back foot again moments later as Connolly brought down Ben Pringle on the edge of the box.
But the Bluebirds were let off the hook once again as Emmanuel Ledesma's curling free-kick brushed the side-netting.
Cardiff looked to have wrestled control of the contest after 60 minutes but the Millers were still creating the better chances as Ledesma stung the hands of Marshall.
Slade looked to have made an inspired substitution on 73 minutes when Macheda, on for Kenwyne Jones, was slipped through on goal by Craig Noone.
He was one-on-one with Adam Collin but it was the Rotherham goalkeeper who came out on top as he produced an inspired save to stop Macheda's low effort sneaking in at the far post.
But Steve Evans' side were hardly sitting back and only the crossbar got in the way of Revell breaking the deadlock with a header from a pin-point Pringle cross.
It was rearguard action for the Millers in the last 10 minutes as Cardiff continued to hoist the ball into the box at every opportunity - but Collin's hands were safe as he comfortably dealt with a barrage of crosses.