The IBM Turboways 622 Mbps PCI MMF ATM 64-bit Universal PCI adapter provides direct access to the ATM network at a dedicated 622 Mbps full-duplex connection. The Turboways 622 Mbps PCI MMF ATM adapter is a short form-factor adapter that interfaces to the system via the PCI bus and connects to the 622 Mbps ATM network via dual-SC type, multi-mode fiber cables. The adapter utilizes 16MB of SDRAM for control and 16MB of SDRAM for packet memory. This ATM adapter also provides a hardware assist for TCP checksum which can provide a performance improvement by minimizing the host CPU cycles.