Silicon Integrated Systems, an ambitious chipset company from Taiwan, formally announced its R659 chipset supporting four-channel RDRAM memory. The core-logic is said to provide tomorrow’s memory bandwidth while being formally announced now, a year after the dead R658 was unveiled, and going in mass production sometimes later. This also the third time this year SiS reminds us about this core-logic.

SiS R659 core-logic is designed to support four-channel RDRAM PC1200 and is able to provide up to 9.60GB/s of peak memory bandwidth. The chipset also includes architectural enhancements for higher performance through faster response time, a feature SiS calls HyperStreaming. In total SiS’ R659 supports up to 16GB of memory, while the forthcoming Prescott CPUs with 800MHz Quad Pumped Bus require just 6.4GB/s of memory bandwidth. 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.

Earlier this year we told you that ASUS and Samsung will support SiS and its R659 platform (see this news-story). Well, there are no doubts Samsung will, as the Korean memory maker constantly supports RDRAM. But where is ASUS? It is true that the final R659 components will not be here till the fourth quarter, but what actually keeps ASUS away from telling us some details about its upcoming product (if there is an upcoming product, not a castle in the sky) or reiterating its intention to support the chipset from SiS? Well, I have no idea.

Even earlier this year we told you about very uncertain prospects of the R659. The problem is probably in the fact that Intel wants its partners to license the every single speed grade or implementation of its Quad Pumped Bus and I expect it will ask chipset makers to license its QPB for Socket T that is coming here in the second quarter next year. In this case SiS may not be able to declare support for Socket T [and possibly faster than 800MHz bus] in R659 from the very beginning due to these reasons. I want to point out that no one will need 9.60GB/s for CPUs with 800MHz PSB consuming just about 6.40GB/s, while 1066MHz and possibly 1200MHz Quad Pumped Bus will not be here for a while and will use Socket T or whatever else Intel may introduce. Even if SiS manages to declare up to 1200MHz Quad Pumped Bus support and first mainboards based on R659 will appear late this year, no one will be able to use such processors on initial R659-based platforms since Intel changes Sockets for higher-end Pentium 4 chips in Q2 2004. As a matter of fact, there will be no sense in getting initial mainboards on SiS R659 support.

As a result of the reasons mentioned above, the life of the R659 in the high-end will be less than two quarters in case it goes into mass production in Q4 2003. And there will be no reasons in getting mainboards based on this rather unique chipset. In fact, it makes some sense for SiS and probably ASUSTeK to postpone the release of the product.

As a consequence, the unique R659 will either be another R658 that was available from only one vendor for a short timeframe or will not be available at all until there is clear need for 9.60GB/s bandwidth, probably in case SiS R659 is able to support Socket T processors.