diff --git a/sys/dev/ata/ata-disk.c b/sys/dev/ata/ata-disk.c
index 338485f74829..59aa2500b867 100644
--- a/sys/dev/ata/ata-disk.c
+++ b/sys/dev/ata/ata-disk.c
@@ -858,9 +858,13 @@ ad_tagsupported(struct ad_softc *adp)
     const char *drives[] = {"IBM-DPTA", "IBM-DTLA", NULL};
     int i = 0;
 
-    /* Promise controllers doesn't work with tagged queuing */
-    if ((adp->controller->chiptype & 0x0000ffff) == 0x0000105a)
-	return 0;
+    switch (adp->controller->chiptype) {
+    case 0x4d33105a: /* Promises before TX2 doesn't work with tagged queuing */
+    case 0x4d38105a:
+    case 0x0d30105a:
+    case 0x4d30105a:  
+        return 0;
+    }
 
     /* check that drive does DMA, has tags enabled, and is one we know works */
     if (adp->controller->mode[ATA_DEV(adp->unit)] >= ATA_DMA &&
diff --git a/sys/dev/ata/ata-dma.c b/sys/dev/ata/ata-dma.c
index d4dc3a57e2d7..4d52518d1392 100644
--- a/sys/dev/ata/ata-dma.c
+++ b/sys/dev/ata/ata-dma.c
@@ -1045,8 +1045,6 @@ promise_timing(struct ata_softc *scp, int devno, int mode)
     case 0x4d38105a:  /* Promise Ultra/Fasttrak 66 */
     case 0x4d30105a:  /* Promise Ultra/Fasttrak 100 */
     case 0x0d30105a:  /* Promise OEM ATA 100 */
-    case 0x4d68105a:  /* Promise TX2 ATA 100 */
-    case 0x6268105a:  /* Promise TX2v2 ATA 100 */
 	switch (mode) {
 	default:
 	case ATA_PIO0:  t->pa = 15; t->pb = 31; t->mb = 7; t->mc = 15; break;
@@ -1060,6 +1058,10 @@ promise_timing(struct ata_softc *scp, int devno, int mode)
 	case ATA_UDMA5: t->pa =  3; t->pb =  7; t->mb = 1; t->mc =  1; break;
 	}
 	break;
+
+    case 0x4d68105a:  /* Promise TX2 ATA 100 */
+    case 0x6268105a:  /* Promise TX2v2 ATA 100 */
+	return;
     }
     pci_write_config(device_get_parent(scp->dev), 0x60 + (devno<<2), timing, 4);
 }
diff --git a/sys/dev/ata/ata-pci.c b/sys/dev/ata/ata-pci.c
index 0697b9771265..c7ef29641151 100644
--- a/sys/dev/ata/ata-pci.c
+++ b/sys/dev/ata/ata-pci.c
@@ -173,9 +173,11 @@ ata_pci_match(device_t dev)
 
     case 0x0d30105a:
     case 0x4d30105a:
+	return "Promise ATA100 controller";
+
     case 0x4d68105a:
     case 0x6268105a:
-	return "Promise ATA100 controller";
+	return "Promise TX2 ATA100 controller";
 
     case 0x00041103:
 	switch (pci_get_revid(dev)) {
@@ -278,15 +280,13 @@ ata_pci_attach(device_t dev)
 			 (pci_read_config(dev, 0x53, 1) & ~0x01) | 0x02, 1);
 	break;
 
-    case 0x4d38105a: /* Promise 66 & 100 need their clock changed */
+    case 0x4d38105a: /* Promise 66 & 100 (before TX2) need the clock changed */
     case 0x4d30105a:
     case 0x0d30105a:
-    case 0x4d68105a:
-    case 0x6268105a:
 	ATA_OUTB(sc->bmio, 0x11, ATA_INB(sc->bmio, 0x11) | 0x0a);
 	/* FALLTHROUGH */
 
-    case 0x4d33105a: /* Promise (all) need burst mode to be turned on */
+    case 0x4d33105a: /* Promise (before TX2) need burst mode turned on */
 	ATA_OUTB(sc->bmio, 0x1f, ATA_INB(sc->bmio, 0x1f) | 0x01);
 	break;