The Aquabus is used to expand the Aquaero, if you connect the OCTO via Aquabus, the Aquaero gets 8 fan ports and the temperature sensors additionally in the Aquasuit, these connections are then only controlled via the Aquaero tab.
The remaining functionality, such as RGBpx continues to run via the OCTO and can only be controlled when the OCTO is connected to the motherboard via USB, the same applies to the firmware updates.
The Aquabus only makes sense if you use another operating system than Windows and want to control as much as possible directly via the Aquaero, since the Aquasuite only runs under Windows.
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