Unsupported gpu architecture 'compute_20'

NVCC src/caffe/layers/reduction_layer.cu
nvcc fatal   : Unsupported gpu architecture 'compute_20'
Makefile:588: recipe for target '.build_release/cuda/src/caffe/layers/reduction_layer.o' failed
make: *** [.build_release/cuda/src/caffe/layers/reduction_layer.o] Error 1

# CUDA architecture setting: going with all of them.
# For CUDA < 6.0, comment the *_50 through *_61 lines for compatibility.
# For CUDA < 8.0, comment the *_60 and *_61 lines for compatibility.
# For CUDA >= 9.0, comment the *_20 and *_21 lines for compatibility.
CUDA_ARCH := #-gencode arch=compute_20,code=sm_20 \
                #-gencode arch=compute_20,code=sm_21
                -gencode arch=compute_30,code=sm_30 \
                -gencode arch=compute_35,code=sm_35 \
                -gencode arch=compute_50,code=sm_50 \
                -gencode arch=compute_52,code=sm_52 \
                -gencode arch=compute_60,code=sm_60 \
                -gencode arch=compute_61,code=sm_61 \
                -gencode arch=compute_61,code=compute_61