Goals from Sam Parkin, Steve Robinson, Alan Reeves, Matt Hewlett and Eric Sabin gave Swindon a deserved 5-2 win at hapless Stockport.
Parkin opened the scoring after a defensive error from Stockport player-manager Carlton Palmer after seven minutes.
Robinson extended the visitors' advantage before Reeves headed home from a Stefani Miglioranzi corner to make it 3-0 on 74 minutes.
County pulled a goal back through Aaron Lescott nine minutes later, but Hewlett made it 4-1 before substitute Rickie Lambert reduced the arrears again near the end.
It was never going to be enough for Palmer's struggling side, who have now won only twice in their last 11 league outings.
Sabin completed the rout for Swindon by firing home in added time as they made sure of revenge on their hosts, who beat them 1-0 at the start of the season.