64-bitDigital Alpha, versions of Sun SPARC, MIPS, IBM AS/4000. the PowerPC and Intel were expected to move to 64 bits at their next generation - PPC 620 and Intel P7. A 64-bit address bus allows the processor to address 18 million gigabytes as opposed to the mere 4 gigabytes allowed with 32 bits. There were in 1996 already hard disks which can hold over 4GB. Floating point calculations can also be more accurate. A 64-bit OS is needed as well to take advantage of the CPU. In 1996 there were only a few 64-bit operating systems, including OS/400, Digital Unix, Solaris (partialy). A 32-bit OS can run on a 64-bit CPU.
Last updated: 2004-05-12