The PA-8200 (PCX-U+), code-named Vulcan, was a further development of the PA-8000. The first systems to use the PA-8200 became available in June 1997. The PA-8200 operated at 200 to 240 MHz and primarily competed with the Alpha 21164. Improvements were made to branch prediction and the TLB. Branch prediction was improved by quadrupling the number of BHT entries to 1,024, which required the use of a two-bit algorithm in order to fit without redesign of surrounding circuitry; and by implementing a write queue that enabled two branch outcomes to be recorded by the BHT instead of one. The number of TLB entries was increased to 120 entries from 96, which reduced TLB misses. The clock frequency was also improved through minor circuit redesign. The PA-8200's die was identical in size to the PA-8000 as improvements utilized empty areas of the die. It was fabricated in the CMOS-14C process.
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