Sun Microsystems Inc will attempt to shrug off the notion that Sparc has run out of steam by introducing its first 64-bit attempt. The part is also a first pass at the Scalable Processor Architecture RISC V9 design. Called the UltraSparc I, it is a 140MHz to 200MHz bi-endian part rated at between 200 and 300 SPECint92 and 250 to 350 SPECfp92 in the first iteration, but designed to progress to 400 SPECint92 and 500 SPECfp92 by rev II, around the middle of 1996. The first product, running at 167MHz, is now expected by the end of October, delivering 250 SPECint92 and 310 SPECfp92. By comparison, first samples of Digital Equipment Corp’s hot new Alpha, the 9.3m transistor 21164, is expected to reach 290 SPECint92 and 440 SPECfp92 in October. First UltraSparc samples are scheduled for the first quarter of next year, volume deliveries by mid-1995, with system implementations toward the end of the year. That is around three to six months behind original expectations. The part, designed by Sun’s Sparc Technology Business, is being fabricated by Sun’s long-time processor partner Texas Instruments Inc in a 0.5 micron four metallisation layer CMOS process. It will later move to 0.35 micron, which should halve the UltraSparc’s vast 315 square millimetre die size next time. It dissipates a hot 30W of power, although that is less than DEC’s 21164. The UltraSparc family is expected to offer a collection of bi-endian parts for systems above the very low end, where microSparc – including its forthcoming 100MHz to 125MHz third iteration – will now be retained. It will supersede the next SuperSparc II revision, although that part is expected to remain Sun’s volume Sparc for at least a year after UltraSparc’s launch. There are no prices yet, but a one-year-old UltraSparc is expected to cost around a tenth of its starting price. UltraSparc is a four-way superscalar part supporting up to four instructions per cycle, a maximum of two integer, two floating point and a single load-store or branch. It includes Sun’s next-generation bus technology, a 128-bit affair running at between a third and a half of the CPU speed: at 167MHz that will be 1.3Gbps peak, 600Mbps sustained. While 32-bit system software and applications will run on UltraSparc unchanged, that new bus complicates upgrading, but Sun is investigating Mbus bridging technology. There is no need any longer for a dedicated video processor: UltraSparc includes on-board processing for up to two Moving Picture Expert Group-2 video decompressions and video manipulation simultaneously. However, to save space for all that work, Sun has also included on UltraSparc what it decribes as a Visual Instruction Set, or common denominator of what it believes to be 30 oft-used graphics instructions, presenting them as an extension to Sparc V9. Even without a major partner betting the company on it, Sun rec-kons Sparc can survive longer than other RISCs, saying it will be fighting for the number two processor spot with PowerPC, with Sparc winning on price-performance. Sparc Technology Business has had 100 en-gineers and a third of its resources tied up in the $50m UltraSparc effort. With a claimed 400 engineers working on Sparc up and down Silicon Valley, it reckons it has as much effort focussed on Sparc development as there is at the Somerset laboratory working on PowerPC. Although it was suggested that Sun’s other Sparc partner, Fujitsu Ltd, may eventually fabricate UltraSparc too, the $500m that the two are planning to spend on joint Sparc development over the next five years will be dedicated mostly to what will follow UltraSparc, Sun says.
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