Description: With the 4-Port Dual Bus PCI Express USB 3.0 card PEXUSB3S42V, you can add four Dual Bus USB 3.0 ports to a PCIe x4-capable PC. The dual bus architecture enhances USB 3.0 performance by transferring data over independent channels to the computer, resulting in faster file transfers. When multiple devices are connected, the maximum bandwidth on traditional single bus USB 3.0 cards is shared across all ports. By utilizing a second host controller chipset, the dual bus transfer channel is shared by only two instead of four ports. By allocating up to 5 Gbit/s to each pair of ports, bottlenecks are reduced, effectively doubling the overall available bandwidth to 10 Gbit/s. With support for UASP (USB Attached SCSI Protocol), this USB 3.0 controller is up to 70% faster than conventional USB 3.0 when used with a UASP-capable enclosure.