diff --git a/comfy/model_patcher.py b/comfy/model_patcher.py
index 3bba7b35b..a09c9f2c0 100644
--- a/comfy/model_patcher.py
+++ b/comfy/model_patcher.py
@@ -41,6 +41,7 @@ import comfy.utils
 from comfy.comfy_types import UnetWrapperFunction
 from comfy.patcher_extension import CallbacksMP, PatcherInjection, WrappersMP
 from comfy.model_management import get_free_memory, get_mmap_mem_threshold_gb, get_free_disk
+from comfy.quant_ops import QuantizedTensor
 
 def need_mmap() -> bool:
     free_cpu_mem = get_free_memory(torch.device("cpu"))
@@ -54,12 +55,6 @@ def to_mmap(t: torch.Tensor, filename: Optional[str] = None) -> torch.Tensor:
     """
     Convert a tensor to a memory-mapped CPU tensor using PyTorch's native mmap support.
     """
-    # Move to CPU if needed
-    if t.is_cuda:
-        cpu_tensor = t.cpu()
-    else:
-        cpu_tensor = t
-    
     # Create temporary file
     if filename is None:
         temp_file = tempfile.mktemp(suffix='.pt', prefix='comfy_mmap_')
@@ -67,6 +62,7 @@ def to_mmap(t: torch.Tensor, filename: Optional[str] = None) -> torch.Tensor:
         temp_file = filename
     
     # Save tensor to file
+    cpu_tensor = t.cpu()
     torch.save(cpu_tensor, temp_file)
     
     # If we created a CPU copy from CUDA, delete it to free memory
@@ -89,37 +85,7 @@ def to_mmap(t: torch.Tensor, filename: Optional[str] = None) -> torch.Tensor:
             pass
     
     weakref.finalize(mmap_tensor, _cleanup)
-    
-    # # Save original 'to' method
-    # original_to = mmap_tensor.to
-    
-    # # Create custom 'to' method that cleans up file when moving to CUDA
-    # def custom_to(*args, **kwargs):
-    #     # Determine target device
-    #     target_device = None
-    #     if len(args) > 0:
-    #         if isinstance(args[0], torch.device):
-    #             target_device = args[0]
-    #         elif isinstance(args[0], str):
-    #             target_device = torch.device(args[0])
-    #     if 'device' in kwargs:
-    #         target_device = kwargs['device']
-    #         if isinstance(target_device, str):
-    #             target_device = torch.device(target_device)
-    #     
-    #     # Call original 'to' method first to move data
-    #     result = original_to(*args, **kwargs)
-    #     
-    #     # NOTE: Cleanup disabled to avoid blocking model load performance
-    #     # If moved to CUDA, cleanup the mmap file after the move
-    #     if target_device is not None and target_device.type == 'cuda':
-    #         _cleanup()
-    #     
-    #     return result
-    
-    # # Replace the 'to' method
-    # mmap_tensor.to = custom_to
-    
+
     return mmap_tensor
                 
 def model_to_mmap(model: torch.nn.Module):
@@ -149,13 +115,13 @@ def model_to_mmap(model: torch.nn.Module):
         - For Parameters: modify .data and return the Parameter object
         - For buffers (plain Tensors): return new MemoryMappedTensor
         """
-        if isinstance(t, torch.nn.Parameter):
-            # For parameters, modify data in-place and return the parameter
-            if isinstance(t.data, torch.Tensor):
-                t.data = to_mmap(t.data)
+        if isinstance(t, QuantizedTensor):
+            logging.debug(f"QuantizedTensor detected, skipping mmap conversion, tensor meta info: size {t.size()}, dtype {t.dtype}, device {t.device}, is_contiguous {t.is_contiguous()}")
             return t
+        elif isinstance(t, torch.nn.Parameter):
+            new_tensor = to_mmap(t.detach())
+            return torch.nn.Parameter(new_tensor, requires_grad=t.requires_grad)
         elif isinstance(t, torch.Tensor):
-            # For buffers (plain tensors), return the converted tensor
             return to_mmap(t)
         return t