When running lspci | grep -i nvidia to check for a GPU, you see “bash: lspci: command not found.” This means the lspci tool itself isn't installed on the system — it's not a sign of a GPU problem.
# CentOS 7.9 sudo yum install pciutils
On Rocky/Ubuntu, just swap yum for the corresponding package manager (Rocky: sudo dnf install -y pciutils; Ubuntu: sudo apt install -y pciutils).
Once installed, run lspci | grep -i nvidia again.