Intel continues to be the dominant processor supplier to Top 500 systems by far. In the systems themselves, IBM and Hewlett-Packard continue their neck-and-neck race, with IBM edging out HP in the current list.
A total of 408 systems (81.6 percent) are now using Intel processors up from 420 systems (80.4 percent) six months ago. AMD's Opteron is the second most commonly used processor, found in 47 systems (9.4 percent), up from 42 systems six months ago. IBM follows with its Power chips in 42 systems (8.4 percent), down from use in 52 systems.
Intel's newest server chip, the Core i7 aka Nehalem-EP, increased its presence in the list with 186 systems compared with 95 six months ago.
Quad-core processors have saturated the Top 500 with 425 systems using them. However, processor with six or more cores can already be found in 25 systems and are expected to proliferate quickly.
In terms of systems providers, IBM leads with 198 systems on the list (39.8 percent) compared to HP with 185 systems (37 percent). Six months ago, HP had 210 systems (42 percent) compared to IBM with 186 systems (37.2 percent). Cray, SGI, and Dell follow with 4.2 percent, 3.4 percent and 3.4 percent respectively.
IBM remains the clear leader in performance with 33.6 percent of installed total performance (down from 35.1 percent), compared to HP with 20.4 percent (down from 23 percent).
The vast majority of Top 500 systems (424 systems) continue to use cluster architectures. Gigabit Ethernet continues to be the leading interconnect, used in 244 systems, followed by InfiniBand with 205 systems, up from 161 a year ago.
The Top 500 list is compiled by Hans Meuer of the University of Mannheim, Germany; Erich Strohmaier and Horst Simon of NERSC/Lawrence Berkeley National Laboratory; and Jack Dongarra of the University of Tennessee, Knoxville.