Jamie Mackie maintained QPR's storming start to the season with a double strike against Leicester at the Walkers Stadium which took Neil Warnock's men five points clear at the summit.
Mackie headed home Adel Taarabt's 12th-minute cross and added a second - his sixth in four games - four minutes from time to seal a 2-0 away win.
Ipswich moved up from fifth to second place with a 2-0 win over Cardiff at Portman Road. Roy Keane's men took the lead on 62 minutes when Adam Matthews headed into his own net and Jason Scotland made it 2-0 16 minutes from time.
Millwall, who started in fourth place, were hit for six against Watford at the New Den.
Jordan Eustace, Jordon Mutch and Marvin Sordell fired the Hornets into a 3-0 half-time lead. Adrian Mariappa grabbed a fourth after the break and, although Liam Trotter pulled a goal back, Danny Graham added a fifth and Martin Taylor a last-minute sixth for the visitors who climbed to fifth place.
Norwich skipper Grant Holt fired what proved to be a winner in the 62nd minute against Preston at Deepdale while late goals from Scott Sinclair and Stephen Dobbie gave Swansea a 2-0 win over Scunthorpe at the Liberty Stadium.
Middlesbrough's revival continued with a 3-1 win over Reading at the Riverside. Barry Robson and Leroy Lita fired Boro 2-0 up and, although Jimmy Kebe's solo effort gave Reading hope before the break, David Wheater headed Robson's corner home on 68 minutes to clinch victory.
Adam Hammill was Barnsley's saviour as they had to settle for a point against Derby at Oakwell. Dean Leacock headed the Rams into a 14th-minute lead but Hammill levelled three minutes into the second half.
Ben Turner's header just before the break proved enough to earn Coventry a 2-1 win against Bristol City at Ashton Gate. Clive Platt had fired the Sky Blues ahead and, after Marvin Elliott's diving header had brought City level, Turner nodded the visitors back ahead.
Ched Evans struck 13 minutes from time to give Sheffield United a 1-0 win over bottom club Portsmouth at Bramall Lane while Crystal Palace and Burnley fought out a goalless draw at Selhurst Park.