GPU usage with PBS

GROMACS version: 2020.5
GROMACS modification: No

Hi everyone, I have a question regarding the GPU/PBS usage with gromacs.

I am running my simulations in one node that has four GPUs and 80 cores. General, I am running four simulations at the same time in this node, using 16 cores for each simulation (8 mpi/2 openMP). So, my PBS script file has:

#PBS -l select=1:ncpus=16:mpiprocs=8:ompthreads=2:ngpus=1

But in this case, all the simulations are using all the four GPUs at the same time.

My question is the following; is possible to control by the PBS file the number of GPUs Gromacs is going to use? I know that I can add the mdrun flag “gpu_id XX”. But this node is part of a big HPC server, so, I would like to control the number of GPUs by the PBS submission.

Thank you