diff --git a/platform/mellanox/mlnx-platform-api/sonic_platform/thermal.py b/platform/mellanox/mlnx-platform-api/sonic_platform/thermal.py
index 1a7d7b8a5c31..28db60474281 100644
--- a/platform/mellanox/mlnx-platform-api/sonic_platform/thermal.py
+++ b/platform/mellanox/mlnx-platform-api/sonic_platform/thermal.py
@@ -267,7 +267,7 @@
     },
     # 3420
     {
-        THERMAL_DEV_CATEGORY_CPU_CORE:(0, 4),
+        THERMAL_DEV_CATEGORY_CPU_CORE:(0, 2),
         THERMAL_DEV_CATEGORY_MODULE:(1, 60),
         THERMAL_DEV_CATEGORY_PSU:(1, 2),
         THERMAL_DEV_CATEGORY_CPU_PACK:(0,1),