nPar partitions are electrically isolated from other nPar partitions within the same chassis. Cells (a unit of processors/IO/memory) make up nPar partitions. Being electrically isolated means that if a nPar partition were to fail due to hardware failure, then the other nPar partitions would continue to work. This is contrasted with vPar partitions which exist within nPar partitions in which a failure at the hardware level for a nPar would affect all vPars within that nPar.