High performance single chip VAX microprocessor
M. Uhler · 2003
Summary form only given. The author describes NVAX, a high-performance, single-chip implementation of the VAX architecture, which is fully compatible with previous VAX implementations. The chip is used in the VAX 6000 model 600 and VAX 4000 model 500 systems. In its highest performance version NVAX runs at 83.3 MHz, and delivers 40.4 SPECmarks and 83.6 transactions per second on the TPC-A benchmark. NVAX is implemented in Digital's 0.75- mu m CMOS 3.3-V technology, contains 1.3 M transistors, and is packaged in a 339-pin PGA. The NVAX design uses RISC (reduced instruction set computer) principles to improve performance. Included on the chip are a 96-entry, fully associative translation buffer, a 2-KB direct-mapped virtual instruction cache, an 8-KB, 2-set associative instruction and data cache and a writeback backup cache controller that interfaces to tag and data RAMs on the module.>