What comes after ModSim 64? Interestingly, no mainstream "ModSim 128" exists because 64-bit address space remains sufficient for all foreseeable engineering problems. However, two trends are reshaping the landscape:
A true ModSim 64 environment runs a —Linux being the dominant choice (CentOS, RHEL, or Ubuntu Server). Windows Server supports ModSim 64, but the vast majority of supercomputing benchmarks favor UNIX-like systems due to lower overhead and finer memory control.