NVIDIA GeForce RTX 3090 with CUDA capability sm_86 is not compatible with the current PyTorch installation.

[Stephenfang51]

Can't get attribute 'SPPF' on <module 'models.common' from
when model = torch.load('yolov5m.pt', map_location='cpu')['model']

[winston1214]

I think you must install torch stable version.
For example, if you use torch==1.7.0

pip install torch==1.7.0+cu110 torchvision==0.8.0+cu110 torchaudio==0.7.0 -f https://download.pytorch.org/whl/torch_stable.html