Silicon Integrated Systems and ASUSTeK Computer are very likely to be in a position to ship the first batch of SiS R659-based mainboards as early as in approximately 4 weeks time, the companies said at Rambus Developer Forum in Taipei, Taiwan, a few hours ago.

SiS R659 core-logic is designed to provide 4-channel RDRAM PC1200 and is able to sport up to 9.60GB/s of peak memory bandwidth – more than enough for present and future Intel Pentium 4 processors with 800MHz Quad Pumped Bus. The chipset also includes architectural enhancements for higher performance through faster response time, a feature SiS calls Advanced HyperStreaming. In total SiS’ R659 supports up to 16GB of memory, while conventional Intel Pentium 4 processors do not address more than 4GB of memory. The R659 North Bridge is to be coupled with the SiS964 I/O controller, which integrates 8 USB 2.0 ports and Serial ATA-150 RAID features.

SiS, ASUS and Samsung have been talking about the R659 chipset since the first quarter 2003, but the actual mainboard powered by the world’s last RDRAM-supporting chipset is now scheduled on December. At least, reviewers may receive the mainboard in 4 weeks time, as we managed to unveil.

ASUS showcased its feature-rich Socket 478 P4S13G mainboard during the show and also demonstrated some performance figures of the R659. According to preliminary benchmarks, a system powered by R659 runs Quake III-based games about 7% faster than a comparable computer, but based on i875P chipset. The R659 does not give any significant advantages in office applications, but provides from 4% to 12% speed increase under workstation software workload.

No mainboard makers except ASUS expressed intention to produce mainboards powered by the R659 with RDRAM support. Given higher cost of such memory compared to high-speed DDR SDRAM, not very tangible performance improvement that is still to be confirmed by independent testers, SiS’ reputation as a company mostly concentrated on cost-effective solutions and some other factors, prospects of R659 seem to be uncertain at this point. Nevertheless, I believe this is still a positive fact that both companies have actually finished the project and did not cancel it.