PCI-based modems have recently been introduced to the industry to replace the need for internal modems in computers without ISA slots. Most PCI-based modems are based on proprietary “windows” modem interfaces and are not supported by IRC (see above on “windows” modems). If an internal modem is desired, use a controller-based ISA modem. If an ISA modem is unable to be accommodated, use an external serial modem.