 It supported 16 to 512 MB of memory.The VAX 4000 Model 600, code-named ""Omega/N+"", was a distributed server, positioned as a high-end VAX 4000 system, introduced on 7 July 1992.It used the KA690 CPU module containing an 83 MHz (12 ns) NVAX microprocessor with and 512 KB of external tertiary cache.