The Comtrol RocketPort uPCI 4J serial port expansion card provides four "native" serial ports utilizing a single 32- or 64-bit PCI card slot and is compatible with all current 3.3 and 5.0 Volt PCI bus architectures. The RJ45 serial ports, mounted on the edge of the card, support RS-232 serial communications at speeds up to 921 Kbps. Every RocketPort serial card features the high-performance RocketPort ASIC chip, consisting of a dedicated 44MHz processor that minimizes host CPU utilization and larger transmit-and-receive buffers than those of 16550 UART chips used in standard PC serial ports and low-end serial cards. RocketPort ASIC technology enables these cards to outperform other serial expansion cards by handling the transmission of large amounts of data more reliably and efficiently. Additionally, RocketPort products do not require the assignment of interrupts, simplifying installation and eliminating conflicts with other server cards.