update comments in xorg.conf snippet to be more clear

MultiMonitorDesktop.mdwn

@@ -70,8 +70,9 @@ It has been confirmed by a number of people that multicard setup (two cards driv
         Driver      "nouveau"
         # Actual PCI location of first card/gpu
         BusID       "PCI:9:0:0"
-        # Actual connector - as reported by /sys/class/drm/card0-xx
-        Option      "ZaphodHeads" "DVI-0"
+        # Actual connector - as reported by /sys/class/drm/card0-xx (except HDMI, which is HDMI-x instead of HDMI-A-x)
+        Option      "ZaphodHeads" "DVI-I-1"
+        # Screen number for that PCI device, i.e. 0, 1, etc.
         Screen      0
     EndSection
     Section "Device"
@@ -79,8 +80,9 @@ It has been confirmed by a number of people that multicard setup (two cards driv
         Driver      "nouveau"
         # Actual PCI location of first card/gpu
         BusID       "PCI:9:0:0"
-        # Actual connector - as reported by /sys/class/drm/card0-xx
-        Option      "ZaphodHeads" "DVI-1"
+        # Actual connector - as reported by /sys/class/drm/card0-xx (except HDMI, which is HDMI-x instead of HDMI-A-x)
+        Option      "ZaphodHeads" "DVI-I-2"
+        # Screen number for that PCI device, i.e. 0, 1, etc.
         Screen      1
     EndSection
     Section "Device"
@@ -88,8 +90,9 @@ It has been confirmed by a number of people that multicard setup (two cards driv
         Driver      "nouveau"
         # Actual PCI location of second card/gpu
         BusID       "PCI:8:0:0"
-        # Actual connector - as reported by /sys/class/drm/card1-xx
-        Option      "ZaphodHeads" "DVI-2"
+        # Actual connector - as reported by /sys/class/drm/card1-xx (except HDMI, which is HDMI-x instead of HDMI-A-x)
+        Option      "ZaphodHeads" "DVI-I-3"
+        # Screen number for that PCI device, i.e. 0, 1, etc.
         Screen      0
     EndSection
     Section "Device"
@@ -97,8 +100,9 @@ It has been confirmed by a number of people that multicard setup (two cards driv
         Driver      "nouveau"
         # Actual PCI location of second card/gpu
         BusID       "PCI:8:0:0"
-        # Actual connector - as reported by /sys/class/drm/card1-xx
-        Option      "ZaphodHeads" "DVI-3"
+        # Actual connector - as reported by /sys/class/drm/card1-xx (except HDMI, which is HDMI-x instead of HDMI-A-x)
+        Option      "ZaphodHeads" "DVI-I-4"
+        # Screen number for that PCI device, i.e. 0, 1, etc.
         Screen      1
     EndSection