Silicon Image's Sil2515 is a native two-port SATA controller. It supports 300 MB/s transfers as well as all current features such as hot plugging and Native Command Queuing.
eSATA can accommodate non-eSATA systems by adding PCI Express or PCI controller cards to PCs. In addition, more and more motherboards are equipped with an eSATA connector. They can be found next to the network, USB and audio ports. It is also possible to use slot adapter modules that allow internal SATA ports to become eSATA compatible.
For notebooks, an external 3.5" hard drive attached via eSATA delivers much better performance than any available 2.5" notebook hard drive. You can, for example, use an internal 2.5" drive while you are traveling and then switch over to an external high-performance drive for home or office use.