AMR (Audio/Modem Riser) is a 46-pin slot on Intel motherboards providing AC97 audio and modem codec connections via a riser card. Used from 1998 to 2003 before integrated audio made it obsolete.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | GND | Ground | GND |
| 2 | BITCLK | AC97 bit clock | BUS |
| 3 | SDATA_OUT | Serial data output | BUS |
| 4 | SDATA_IN | Serial data input | BUS |
| 5 | SYNC | AC97 sync | BUS |
| 46 | VCC | 3.3V power | PWR |