diff --git a/python/llm/src/ipex_llm/transformers/npu_models/mp_models_base.py b/python/llm/src/ipex_llm/transformers/npu_models/mp_models_base.py
index 9763a122e21..27e4469fd99 100644
--- a/python/llm/src/ipex_llm/transformers/npu_models/mp_models_base.py
+++ b/python/llm/src/ipex_llm/transformers/npu_models/mp_models_base.py
@@ -472,7 +472,7 @@ def layer_norm(self, hidden_states, layernorm_weight):
         )
         eps = self.constant(self.rms_norm_eps)
         hidden_states = self.eltwise_div(hidden_states, self.sqrt(self.eltwise_add(variance, eps)))
-        if os.environ.get("IPEX_LLM_NPU_DRIVER_VERSION", "0") == "1":
+        if os.environ.get("IPEX_LLM_NPU_DRIVER_VERSION", None) in ["5716", "5733"]:
             # to support special drivers
             hidden_states = self.convert_to_fp16(hidden_states)
         else: