Add a rs 232 serial port to your standard or small form factor computer through a pci express expansion slot native single chip, single lane pci express 48% less cpu load, and increased performance pre configured for low profile half height systems but includes a full profile bracket for versatility easy to install and use with full step by step instructions saving time and hassle add a rs 232 serial port to your standard or small form factor computer through a pci express expansion slot the pex1s553lp pci express serial card turns a pci express slot into an rs232 db9 serial connection'. '.strtoupper('t')he card is constructed using a native single chip design that lets you harness the full capability offered by pci express pcie, while reducing the load applied to the cpu by as much as 48% over conventional bridge chip serial cards'. '.strtoupper('t')he pci express rs232 serial adapter card is compatible with a broad range of operating systems, including windows® 2000 xp 2003 vista windows 7 server 2008 r2 32 and 64 bit, linux kernel 2.6.11 and up, and ships with a low profile half height bracket installed, but includes an optional full profile bracket that lets you add a serial port to virtually any computer regardless of the case form factor'. '.strtoupper('t')his product is a replacement for our pex1s552lp card'. '.strtoupper('b')acked by a startech.com lifetime warranty and free lifetime technical support'. '.strtoupper('w')hats in the box 1 port pci express serial card full profile bracket driver cd instruction manual