Graph A shows Alpha processors' performance improvement since Microsoft introduced the Alpha version of Windows NT in 1993. For comparison, the chart includes several key Intel processors from the same period. The listed dates are not the dates of each processor's introduction. They are the dates of the processors' benchmarks. These two dates are frequently, but not always, the same.
The chart's performance numbers come from the SPEC95 benchmark of the Standard Performance Evaluation Corporation (http://www.specbench.org). The Alpha 21064 and 21066 and Intel 60MHz Pentium processors do not have SPEC95 numbers available, so I approximated SPEC95 speeds based on SPEC92 benchmarks to demonstrate those processors' relative performance. The 21364, 21464, and Merced processors' performance data is an estimate of those systems' expected speed.
The low-cost Digital, Mitsubishi, and Samsung 21066 and 21164PC chips were modified versions of Digital's original design of these chips. The chart doesn't show the soon-to-be-available 21264PC. This processor's performance numbers were not available at press time.
Finally, the 21164's performance numbers don't reflect the 700MHz air-cooled or 767MHz cryogenically cooled implementations. The 700MHz chip's benchmarks aren't available, and because no other processors offer cryogenic cooling, readers can't compare the 767MHz machine to other systems.