UltraSPARC IV
| Industry | Computer hardware |
|---|---|
| Founded | February 24, 1982 |
| Founder | Vinod Khosla, Andy Bechtolsheim, Scott McNealy, Bill Joy |
| Headquarters | Santa Clara, California , United States |
| Products | UltraSPARC IV, UltraSPARC IV+ |
The UltraSPARC IV Jaguar processor and its follow-up, the UltraSPARC IV+ Panther, were developed by Sun Microsystems and produced by Texas Instruments. Representing the fourth iteration in the UltraSPARC lineup, these microprocessors utilize the 64-bit SPARC V9 instruction set architecture. Initially, the UltraSPARC IV was intended to be replaced by the UltraSPARC V Millennium, but this project was discontinued after the unveiling of the Niagara (later known as UltraSPARC T1) in early 2004. Ultimately, Fujitsu's SPARC64 VI became its successor.
Both the UltraSPARC IV and UltraSPARC T1 emerged from Sun's Throughput Computing program, which also encompassed designs like UltraSPARC V Millennium and Gemini. Among these, only the UltraSPARC IV and UltraSPARC T1 reached commercial production. Unlike the block multithreading strategy employed by the Millennium and Niagara, the UltraSPARC IV adopted chip-multithreading (CMP), featuring multiple independent single-thread cores.
Launched in March 2004, the UltraSPARC IV marked Sun's debut in multi-core SPARC processors. It integrates two upgraded UltraSPARC III cores that share an L2 cache of up to 16 MB, with distinct L2 cache tags assigned to each core. Enhancements encompass refined instruction fetching, increased store bandwidth, improved data prefetching mechanisms, and a floating-point adder designed to manage a broader range of NaN and underflow scenarios, thereby minimizing exceptions. The chip comprises 66 million transistors on a die measuring 356 mm2, manufactured using a 0.13 μm process by Texas Instruments.
Introduced in mid-2005, the UltraSPARC IV+ continued with a dual-core configuration featuring upgraded cores and integrated L2 cache, fabricated with a 90 nm process technology. Its initial clock rate was 1.5 GHz—lower than the targeted 1.8 GHz—but this frequency was raised to 2.1 GHz by April 2007. The processor contains approximately 295 million transistors.
Sun launched server systems powered by the UltraSPARC IV in September 2004 and those utilizing the UltraSPARC IV+ in September 2005. Server models such as Sun Fire V490, V890, E2900, E4900, E6900, E20K, and E25K incorporated these processors across configurations ranging from 4 to 72 sockets (equating to 8 to 144 cores).
The introduction of the UltraSPARC IV+ played a significant role in Sun reclaiming a leading position within the RISC/UNIX server market in 2006, contributing positively to revenue growth.