Question about Icy Box Raidsonic IB-AC6104 4 new USB 3.0 devices

I see no problem there. Otherwise, I'll buy the part back for you.
However, as described in the article, you cannot necessarily operate 3 hard disks in parallel. That's why there is an additional 5V connection on the part for higher power consumption. USB 3.0 = Min 150mA - max. 900mA. In the future, USB 3.1 Type C = 100W. At 20V, that would be 5A!