第一种方法是检查NVIDIA CUDA编译器NVCC的版本

$ nvcc --version
nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2019 NVIDIA Corporation
Built on Wed_Oct_23_19:24:38_PDT_2019
Cuda compilation tools, release 10.2, V10.2.89

鉴于Ubuntu 20.04系统上安装了NVIDIA驱动程序，以下命令还将显示CUDA版本：

$ nvidia-smi 
Wed Jan 15 11:48:58 2016       
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 440.44       Driver Version: 440.44       CUDA Version: 10.2     |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|===============================+======================+======================|
|   0  GeForce GTX 106...  Off  | 00000000:01:00.0  On |                  N/A |
| 24%   35C    P8     6W / 120W |    330MiB /  6077MiB |      0%      Default |
+-------------------------------+----------------------+----------------------+

+-----------------------------------------------------------------------------+
| Processes:                                                       GPU Memory |
|  GPU       PID   Type   Process name                             Usage      |
|=============================================================================|
|    0      1090      G   /usr/lib/xorg/Xorg                            18MiB |
|    0      9782      G   /usr/lib/xorg/Xorg                            74MiB |
|    0     10001      G   /usr/bin/gnome-shell                         113MiB |
|    0     11724      G   gnome-control-center                           1MiB |
+-----------------------------------------------------------------------------+

如果我们没有更改默认的CUDA安装路径，我们也可以通过查看/usr/local/cuda/version.txt文件的内容来检查CUDA版本：

$ cat /usr/local/cuda/version.txt
CUDA Version 10.2.89

检查安装的CUDA Toolkit包：

$ dpkg -l | grep cuda-toolkit
ii  cuda-toolkit-10-2 10.2.89-1 amd64    CUDA Toolkit 10.2 meta-package