Packaging
The Alpha 21264 was packaged in a 587-pin ceramic interstitial pin grid array (IPGA).
Alpha Processor, Inc. later sold the Alpha 21264 in a Slot B package containing the microprocessor mounted on a printed circuit board with the B-cache and voltage regulators. The design was intended to use the success of slot-based microprocessors from Intel and AMD. Slot B was originally developed to be used by AMD's Athlon as well, so that API could obtain materials for the Slot B at commodity prices in order to reduce the cost of the Alpha 21264 to gain a wider market share. This never materialized as AMD chose to use Slot A for their slot-based Athlons.
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