PC OEMs have reason to watch Sun Microsystems Inc.'s new UltraSparc III processor closely, even though it will be used only in Sun's own computers.
The 64-bit chip, unveiled here last week, will support vast server arrays featuring more than 100 UltraSparc III processors operating in parallel, according to Sun executives. That far exceeds competing OEM systems based on MPUs from the likes of Intel Corp., which are typically configured for four- or eight-way servers.
Feeding into the high-end-and high-margin-server/workstation battle being waged by both suppliers and OEMs, Sun claims its new processor features an out-of-cache address bandwidth of 9.6 Gbytes/s. The chip's 4.8-Gbyte/s data rate is up to four times faster than other 32- or 64-bit processors, according to the Mountain View, Calif., company.
Though about 18 months behind schedule-so late in fact that the company moved the MPU's process geometry from 0.18-micron to a 0.15-micron design rule-the chip includes novel features such as an embedded memory controller. According to Fadi Azhari, Sun's UltraSparc marketing manager, the on-chip controller enables faster access to memory than processors using a discrete chipset and north-bridge bus. In fact, the UltraSparc III is among the first next-generation processors to integrate the north bridge, following Transmeta Corp.'s Crusoe.
More important, the UltraSparc III includes an on-chip scalable feature that, as previously mentioned, allows more than 100 processors to be connected at once. This far exceeds the ability of Intel's 32-bit processors, according to Azhari, or even its upcoming Itanium and McKinley 64-bit MPUs, which at most support eight-way systems. He added that some OEMs, such as Unisys Corp. and NEC Corp., have designed their own custom chipsets to allow for larger multiprocessor configurations based on Intel chips.
Sun perceives no immediate threat from Intel's 64-bit Itanium, which is slated to be unveiled later this year, Azhari said, or from the successor McKinley processor, set to debut in late 2001. He added that Intel's 64-bit MPU strategy requires developers moving up the processor food chain to write entirely new software or recompile existing 32-bit X86-based programs.
"They have no easy binary compatibility with their new IA-64 architecture," Azhari said. "Sun has found that binary compatibility in all new systems is what customers want most. UltraSparc III is backward compatible with all its predecessor chips, and will be compatible with all future processors."
Intel, Santa Clara, Calif., has long maintained that its IA-64 processors will run legacy X86 software through a separate on-chip core. The company conceded that new 64-bit programs must be written to run on its Itanium and McKinley processors, but claimed recently that 350 application developers have so far committed to port programs to the devices
At a press conference here last week, Sun laid out its processor road map, describing a 0.13-micron UltraSparc IV to be introduced in 2002. The device will embed additional functions, including more cache and possibly a south bridge, Azhari said. A more extensively redesigned UltraSparc V is slated to appear in 2003 as Sun tries to return to a three-year cycle of upgrading its processor architecture.
One spec that Sun didn't earn bragging rights to is clock speed. The UltraSparc III initially will ship with a top frequency of 750 MHz, although Azhari said a 900-MHz speed grade will be available in the first quarter when foundry Texas Instruments Inc. begins to use copper interconnects in the chip's seven metal layers.