Fusion-IO SSD uses PCIe x4 slot and offers 1.4Gb/s Write Speed
 

As a leading provider of enterprise solid-state technology and high-performance I/O solutions, Fusion-IO announces its latest product ioDrive Duo, which claims to be the fastest and most innovative SSD in the world.

Coming in capacities of 160/320/640GB and maximum 1.28TB, ioDrive Duo is based on PCI Express x8 or PCI Express 2.0 x4 standards to deliver 20GB/s of raw throughput. The 32k packet size provides sustained read/write speed of 1.5/1.4GB per second, with latency of less than 50 µsec.

http://en.expreview.com/2009/03/12/f...drive-duo.html