The Fujitsu Futro S900 was built up to 2013, and only had one SATA port from the factory. [Jan] wanted to add another as this would make the device more useful as a network attached storage server.

The IntelliProp IPP-SA128A-PM (SATA Port Multiplier with Sandbox) device is an IP core that provides SATA Port Multiplier functionality with support for up to 15 SATA storage devices. The IP core is ...

The technology is great for high data- throughput environments. Each SATA port on the card is capable of managing up to 4 Tbytes of storage. As many as eight drives can be connected at once.

Honestly, I'd just consider getting a PCI-E SATA controller card and using that. It has the advantage of being useful if you ever upgrade your system again. It might save you money now and ...