Ryder has been in incredible form this summer as he plays with the sort of freedom that comes with not worrying about his international career, and smacked 62 off just 37 balls to help Wellington set a big total of 197 for four in their 20 overs.
He hit five fours and five sixes and put on 90 for the first wicket with Tamin Iqbal (68 off 49) but his innings was overshadowed in the end by Devcich and Scott who went on a scoring spree.
Devcich (92 off 57) and Scott (74 off 49) put on a record 165 for the first wicket before Scott departed to Ryder's bowling. English professional Steven Croft (17 off 10) then maintained the momentum to ensure ND got home with one over to spare.
The ease of their chase and brutality of their hitting was a treat for the holiday crowd at Bay Oval. None of Wellington's bowlers escaped treatment - the first two 50s came off 32 balls each but the third 50 came off just 19 deliveries as Devcich and Scott put the hammer down.
The result sees Northern Districts jump ahead of Otago at the head of the HRV Cup table but they have played one more game than the Volts.
Late heroics from Gareth Andrew saw Canterbury sneak past Central Districts in Nelson today to collect their first win of the season.
The Wizards looked to be in trouble at 72-5 in the 13th over as they fell dangerously short of the required run rate in their chase for 153 for victory, but Andrew saw them home with 53 off just 25 balls. His innings included four fours and four sixes and he found good support from Todd Astle (25 off 19) as the pair put on 77 for the sixth wicket in just six overs.
Earlier Central Districts, looking for just their second win of the competition, posted a useful 152-8 with Mathew Sinclair (38 off 35) and Kieran Noema-Barnett (36 off 22) the main contributors.
Points table: Northern Districts 20, Otago 16, Wellington 16, Auckland 8, Canterbury 4, Central Districts 4.