Connectors are where the issue is and there is a difference even if they fit in the same plugs and power can still go through them.
From your link
> Compared to the original 12VHPWR connector, the new 12V-2x6 connector has shorter sensing pins (1.5mm) while the conductor terminals are 0.25mm longer
From your link
> Compared to the original 12VHPWR connector, the new 12V-2x6 connector has shorter sensing pins (1.5mm) while the conductor terminals are 0.25mm longer