AMR is an acronym that full form is Audio Modem Riser. It is commonly known as AMR. It is a riser expansion slot plotted on the motherboards of some Pentium III, Pentium 4, Duron, and Athlon personal computers.
The AMR slot was originally designed by Intel to interface with chipsets and provide analog functionality, like sound cards and modems, on an expansion card.
AMR contains two rows of 23 pins, total 46 pins. It provides an easy and inexpensive way to incorporate sound cards and modems in a particular system. It uses Analog I/O audio functions. These audio functions require two things a software driver and modem circuit. Now a day, AMR is superseded by the Advance Communication Riser (ACR).
Image of AMR: