diff --git a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/hwsku.json b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/hwsku.json
index 9eaac1e2cf..3593da62c7 100644
--- a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/hwsku.json
+++ b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/hwsku.json
@@ -191,6 +191,9 @@
         },
         "Ethernet504": {
             "default_brkout_mode": "1x800G[400G,200G,100G,50G,40G,25G,10G]"
+        },
+        "Ethernet512": {
+            "default_brkout_mode": "1x25G[10G]"
         }
     }
 }
diff --git a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/port_config.ini b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/port_config.ini
index 591fe2a7d4..6ba6991bd0 100644
--- a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/port_config.ini
+++ b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/port_config.ini
@@ -79,3 +79,4 @@ Ethernet480     480,481,482,483,484,485,486,487     etp61     61
 Ethernet488     488,489,490,491,492,493,494,495     etp62     62
 Ethernet496     496,497,498,499,500,501,502,503     etp63     63
 Ethernet504     504,505,506,507,508,509,510,511     etp64     64
+Ethernet512     512                                 etp65     65
diff --git a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/sai_5600.xml b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/sai_5600.xml
index b9ef3af7a8..7fe318fc08 100644
--- a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/sai_5600.xml
+++ b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/ACS-SN5600/sai_5600.xml
@@ -25,7 +25,7 @@
         <issu-enabled>1</issu-enabled>
 
         <!-- Number of ports in the following port list -->
-        <number-of-physical-ports>64</number-of-physical-ports>
+        <number-of-physical-ports>65</number-of-physical-ports>
 
         <!-- List of ports in the device -->
         <ports-list>
@@ -306,7 +306,7 @@
             <port-info>
                 <local-port>153</local-port>
                 <width>8</width>
-        <module>26</module>
+                <module>26</module>
                 <breakout-modes>3</breakout-modes>
                 <port-speed>1536</port-speed>
             </port-info>
@@ -489,6 +489,13 @@
                 <breakout-modes>3</breakout-modes>
                 <port-speed>1536</port-speed>
             </port-info>
+            <port-info>
+                <local-port>257</local-port>
+                <width>1</width>
+                <module>64</module>
+                <breakout-modes>0</breakout-modes>
+                <port-speed>64</port-speed>
+            </port-info>
         </ports-list>
     </platform_info>
 </root>
diff --git a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/platform.json b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/platform.json
index fdc689855c..a3bd96c7cd 100644
--- a/device/mellanox/x86_64-nvidia_sn5600_simx-r0/platform.json
+++ b/device/mellanox/x86_64-nvidia_sn5600_simx-r0/platform.json
@@ -1277,6 +1277,13 @@
                 "4x200G[100G,50G,25G,10G]": ["etp64a", "etp64b", "etp64c", "etp64d"],
                 "8x100G[50G,25G,10G]": ["etp64a", "etp64b", "etp64c", "etp64d", "etp64e", "etp64f", "etp64g", "etp64h"]
             }
+        },
+        "Ethernet512": {
+            "index": "65",
+            "lanes": "512",
+            "breakout_modes": {
+                "1x25G[10G]": ["etp65"]
+            }
         } 
     }
 }