diff --git a/sys/dev/ata/ata-dma.c b/sys/dev/ata/ata-dma.c
index ea4c6d24fffc..5db72139743e 100644
--- a/sys/dev/ata/ata-dma.c
+++ b/sys/dev/ata/ata-dma.c
@@ -371,6 +371,22 @@ ata_dmainit(struct ata_softc *scp, int device,
 	/* we could set PIO mode timings, but we assume the BIOS did that */
 	break;
 
+    case 0x74111022:	/* AMD 766 */
+	if (udmamode >= 5) {
+	    error = ata_command(scp, device, ATA_C_SETFEATURES, 0, 0, 0,
+				ATA_UDMA5, ATA_C_F_SETXFER, ATA_WAIT_READY);
+	    if (bootverbose)
+		ata_printf(scp, device,
+			   "%s setting UDMA5 on AMD chip\n",
+			   (error) ? "failed" : "success");
+	    if (!error) {
+	        pci_write_config(parent, 0x53 - devno, 0xc6, 1);
+		scp->mode[ATA_DEV(device)] = ATA_UDMA5;
+		return;
+	    }
+	}
+	/* FALLTHROUGH */
+
     case 0x74091022:	/* AMD 756 */
 	if (udmamode >= 4) {
 	    error = ata_command(scp, device, ATA_C_SETFEATURES, 0, 0, 0,
@@ -380,7 +396,7 @@ ata_dmainit(struct ata_softc *scp, int device,
 			   "%s setting UDMA4 on AMD chip\n",
 			   (error) ? "failed" : "success");
 	    if (!error) {
-	        pci_write_config(parent, 0x53 - devno, 0xc3, 1);
+	        pci_write_config(parent, 0x53 - devno, 0xc5, 1);
 		scp->mode[ATA_DEV(device)] = ATA_UDMA4;
 		return;
 	    }
@@ -467,7 +483,8 @@ ata_dmainit(struct ata_softc *scp, int device,
 		if (bootverbose)
 		    ata_printf(scp, device, "%s setting UDMA2 on %s chip\n",
 			       (error) ? "failed" : "success",
-			       (scp->chiptype == 0x74091022) ? "AMD" : "VIA");
+			       ((scp->chiptype == 0x74091022) ||
+				(scp->chiptype == 0x74111022)) ? "AMD" : "VIA");
 		if (!error) {
 	            pci_write_config(parent, 0x53 - devno, 0xc0, 1);
 		    scp->mode[ATA_DEV(device)] = ATA_UDMA2;
diff --git a/sys/dev/ata/ata-pci.c b/sys/dev/ata/ata-pci.c
index 6319e207c0d6..1371f76a40aa 100644
--- a/sys/dev/ata/ata-pci.c
+++ b/sys/dev/ata/ata-pci.c
@@ -158,6 +158,9 @@ ata_pci_match(device_t dev)
     case 0x74091022:
 	return "AMD 756 ATA66 controller";
 
+    case 0x74111022:
+	return "AMD 766 ATA100 controller";
+
     case 0x02111166:
 	return "ServerWorks ROSB4 ATA33 controller";
 
@@ -307,7 +310,8 @@ ata_pci_attach(device_t dev)
 	break;
 
     case 0x05711106:
-    case 0x74091022: /* VIA 82C586, 82C596, 82C686 & AMD 756 default setup */
+    case 0x74091022:
+    case 0x74111022: /* VIA 82C586, '596, '686 & AMD 756, '766 default setup */
 
 	/* set prefetch, postwrite */
 	pci_write_config(dev, 0x41, pci_read_config(dev, 0x41, 1) | 0xf0, 1);