nvtop

Despite the name, this also works with AMD GPUs and is generally the best tool for tracking what your GPUs are up to on your system

btop

btop now has GPU monitoring, which is convenient if you have 1 or 2 GPUs.

If you’re distro doesn’t have support w/ 1.3.0 you will need to compile it yourself. Luckily, it’s pretty easy:

# https://github.com/aristocratos/btop/#compilation-linux
git clone https://github.com/aristocratos/btop
cd btop
make
sudo make install