Aberdeen have rejected a reported third bid for winger Jonny Hayes.
It's thought City upped their bid to £600,000 after two previously rejected offers of £500,000.
Aberdeen want more like £1m so have refused to sell with Derek McInnes saying any chance of a deal is dead.
It's unknown if Cardiff will make a final attempt before the window closes tonight.
Bristol Rovers striker Matty Taylor has been linked with Cardiff interest despite him being on the verge of a move to Bristol City. There has been no confirmation as to how accurate the rumours are regarding Taylor and any Cardiff link.
Blackburn's Liam Feeney is another name linked with 'reports' City may have made a bid for him that was rejected.