ryujin ii 360 aio pump display

Can anyone tell me how the Rog Ryujin II 360 AIO gets it's pump speed info ? Armoury Crate shows the pump speed but the display shows the AIO pump rpm at 0. Without a connection to the motherboard's AIO pump connector, how does it get it's AIO pump rpm info? HWinfo64 and AIDA64 do not show pump...