The Saints were beaten 2-0 at home by a Barton Rovers side who recorded back-to-back holiday wins, Connor Calcutt after 10 minutes and Jason Blackett just before the break, ending Chalfont`s good start to 2016-17 campaign.
Farnborough moved top after edging the Hampshire derby at Cherrywood Road by the odd goal in seven in front of 432 against Fleet Town.
Veteran prolific marksman Jamie Cureton found his scoring boots to bag a hat-trick for Boro, with Josh Huggins adding the other, outgunning a Rob Carr brace for the visitors and one from Craig Davis.
Potters Bar Town, AFC Dunstable and Hanwell Town all suffered first defeats of the season.
The Scholars were edged out 3-2 at Chestnut Avenue by Northwood, who came back from being Ashley Nathaniel-George and Ryan Forde goals down by the 35th minute to win, thanks to Myles Stephenson on 37 minutes, Ryan Debattista on 51 minutes and then Louis Bircham on 66 minutes.
AFC Dunstable lost the battle of the new boys, 2-1 at AFC Kempston Rovers, who fell behind to an 11th minute Jermaine Hall goal, but responded through Sam Johnson on 72 minutes and new signing Danny Watson`s third goal of the weekend in injury-time.
Hanwell lost the derby against Uxbridge 3-0 at Honeycroft, with Abobaker Eisa sandwiching a Matty Woods brace for the Reds.
Beaconsfield SYCOB recorded their first three-point haul at new boys Kidlington, who have also yet to win.
And the visitors did it in style, hitting a nap hand without reply, with Nathan Minhas netting a hat-trick and Oli McCoy and Charlie Losasso singles.
Marlow made it four wins from six games with a 2-0 win at Love Lane against Petersfield Town, courtesy of second half goals from Lewis Gabbidon and Anaclet Odhiambo.
Royston Town ensured relegated Histon`s poor start to the season continued with a fifth defeat in six, goals in either half from Gary Cohen and Spyros Mentis winning it for the Crows at Garden Walk.
Egham Town won the derby at home to new boys Ashford Town (Middx) with Brendan Matthew bagging a brace sandwiched by a Reece Yorke effort, with Dan Fleming replying.
Aylesbury United won local bragging rights with a 1-0 victory at Aylesbury FC, thanks to Sonny French`s 77th minute effort.
Elsewhere, Lewis Wilson broke the deadlock to give Arlesey Town a 72nd minute lead at the New Eyrie against Bedford Town before the Eagles equalised through a Tony Williams own goal less than two minutes later in the 1-1 draw.
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