Add 4 high speed rs 232 serial ports to your computer with a buffered serial card from startechcom the card uses a 16 byte buffer in both the receive and transmit channels simultaneously reducing the number of cpu interrupts and improving system performance compatible with both 33 and 5 volt motherboards and uses db9 connectors for use with a wide range of serial peripherals suitable for industrial applications this card is compatible with a wide range of operating systems including win