Question of DCC op in newer Atlas locos

[Power Stroke]

Over the last few months I have been able to pick up 4 "inoperative" new Atlas locomotives on ebay for 30.00 or less. When recieved, the first thing I noticed is the NCE equipped logo on the box. 2 ran, but erratically, 2 did nothing but flash the lights. I operate DC so I expect issues from DCC locos, and as such I have spare analog boards for the models I run.
The models are GP-40, and U23B. Upon disassembly, I noted the boards installed all say 8-40CW instead of the correct model designation. Does this matter? Is Atlas installing the incorrect boards or will any DCC board work, as long as the motor contacts line up?
Two of the locos were purchased from hobby shops, so out of the box, you'd think they'd be checked out or sent back.
Install of analog boards got all 4 working perfectly, like a brand new loco should.
Any thoughts?

[djconway]

Most of Atlas' locos will use one of three  or four boards, based on the spacing of the circuit board mounting tabs.  So an 8-40 board may be the same as a GP-40.

[mu26aeh]

That would be the NCE N12A0 decoder, which is decoder for the N scale Atlas GP40-2, Dash 8-40B, U25B, U23B, B23-7, 30-7, 36-7, GP38, SD25, Trainmaster, etc.  Etc including the 8-40C, CW.  The nice thing about this decoder is the 4 pads at the front, underside can be used with the ditch light board available separately from Atlas if you want to add ditch lights to any of the models listed.