GRES: other generic resources (like GPUs). The 512GB RAM is shared among the four nodes.
sinfo -o "%50N %10c %20m %30G "
NODELIST CPUS MEMORY GRES
slurm[1-4] 64 515879+ (null)
sinfo --nodes=slurm[1] -o "%50N %10c %20m %30G "