The i-tec USB 3.0 hub can theoretically connect 16 external hard drives as it offers 16 USB 3.0 ports. However, it is primarily designed for charging devices, with each port providing up to 10 W of power. For use as a "cheap server" with external hard drives, it could work, but the power supply could be a limit, as the hub has a maximum output of 90W. This may not be sufficient for many hard drives as they often require more power. It is important to check the power requirements of the hard drives to ensure that the hub can supply them with sufficient power.