Unpacking nvidia-340 (340.107-0ubuntu0~gpu18.04.1) ... dpkg: error processing archive /var/cache/apt/archives/nvidia-340_340.107-0ubuntu0~gpu18.04.1_amd64.deb (--unpack): trying to overwrite '/lib/udev/rules.d/71-nvidia.rules', which is also in package nvidia-kernel-common-396 396.45-0ubuntu0~gpu18.04.2 dpkg-deb: error: paste subprocess was killed by signal (Broken pipe) Errors were encountered while processing: /var/cache/apt/archives/nvidia-340_340.107-0ubuntu0~gpu18.04.1_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)
Use the command below and it will resolve the "attempt to overwrite error" with the mighty power of dpkg.
sudo dpkg -i --force-overwrite /var/cache/apt/archives/nvidia-340_340.107-0ubuntu0~gpu18.04.1_amd64.deb //Note the last /var....amd64.deb part, which is the file path name you reported the error
Then run the command below to fix any broken packages.
sudo apt -f install