StarTech.com 4 Port PCI Express Serial Card w/ Breakout Cable

The PEX4S552B Serial PCI Express card lets you add four RS232 serial ports using a single PCIe expansion slot. The serial card features a native single chip design that provides optimum reliability and speed, while reducing the CPU load by as much as 48% over conventional serial cards that utilize a "bridge chip" for communication with the host PCI Express bus - a cost-effective solution for connecting legacy serial devices to modern PCIe-enabled computers.