diff --git a/auto_gptq/quantization/gptq.py b/auto_gptq/quantization/gptq.py
index ef72f10..989a8f4 100644
--- a/auto_gptq/quantization/gptq.py
+++ b/auto_gptq/quantization/gptq.py
@@ -23,7 +23,7 @@ class GPTQ:
         W = layer.weight.data.clone()
         if isinstance(self.layer, nn.Conv2d):
             W = W.flatten(1)
-        if isinstance(self.layer, transformers.Conv1D):
+        if isinstance(self.layer, transformers.pytorch_utils.Conv1D):
             W = W.t()
         self.rows = W.shape[0]
         self.columns = W.shape[1]