A 550 Mhz Alpha Microprocessor Targeted At PC Applications
A SS0MHz Alpha microprocessor targeted ut PC applications i s described. The chip has been fabricated in Mitsubishi's 0.3um twin-well four-layer-metal CMOS process technology. It includes 3.SM transistors i n a I .43cm2 die and is estimated t o deliver 14.3 SPECint9.5 and 17.0 SPECfp9S at S33MHz. The chip employs pipelined Synchronous Burst SRAM interface and supports MVI (Motion Video Instructions) for MPEG-2 encodeldecode. I t i s estimated to deliver 30framesls DID play-back with stereo quality audio. Introduction This multi-media enhanced, quad-issue, 550MHz Alpha architecture microprocessor, the Alpha 21 164PCII 1, i s designed for PC applications. The design i s an extension of an existing RISC microprocessor, the Alpha 21 164[2,3]. 'The design objectives of the 21164PC were t o achieve leadership performance on a die size of less than 1.5cm2 and to realize low system cost. This would facilitate in bringing Alpha's performance to the midrange desktop PC market. In order to minimize time to market, the part of the 21 164PC design was leveraged from the 21 164. Table 1 shows the chip statistics. The availability and affordable pricing of the high performance SRAMs for building the offFigure 1 . The 21 I64PC photomicrograph C o s t and Performance Tradeoffs chip level-two (L2) cache enabled removal of on-chip 96KB L2 cache. This change reduced the chip's die area by almost origillal 21 164, the 21164PC i s able to use the Same core logic chipsets. Figure 1 shows a photomicrograph of the Module and microprocessor costs are important factors reduce the cost of the 21 164, the design team first focused o n the die area, one of the key variable i n production cost. 30%. By keeping the bus interface wi th the for Alpha chip to penetrate volume PC market. In order to