Please check the serial number on the controller which include or later than below serial number. It has fixed the MacPro hardware detective issue.
ARC-1880IXL-12: Y039CACUAR300013
ARC-1880IXL-8: Y039CACTAR200001
ARC-1880IX-12: Y039CACQAR300001
ARC-1880IX-16: Y039CARUAR600001
ARC-1880IX-24: Y039CACSAR800001
ARC-1880X: Y038CACPAR200070
ARC-1880I: Y039CACOAR200001
Tags: ARC-1880, Mac Pro