Communications and networking riser

[1] Introduced by Intel in 2000,[2] CNR slots were once commonly found on Pentium III–class motherboards, but have since been phased out in favor of on-board or embedded components.

[4] As with the audio/modem riser (AMR), CNR had the cost savings potential for manufacturers by removing analog I/O components from the motherboard.

This allowed the manufacturer to only certify with the Federal Communications Commission (FCC) for the CNR card, and not the entire motherboard.

Its principal advantage over CNR was the backwards-compatible slot layout which allowed it to use both AMR and ACR cards.

CNR was both capable of being either software based (CPU-controlled) or hardware accelerated (dedicated ASIC), and was plug-and-play compatible.