SiS645 DDR333 chipset for Pentium 4
Silicon Integrated Systems has begun to sample the SiS645, an Open Architecture DDR333 chipset for the Pentium 4. Look at the snazzy block diagram at the bottom. Unlike the SiS735, this is not an integrated "one-chip" solution; it keeps the traditional north and south bridges separate. The SiS961 South Bridge features something called MuTIOL (Multi-Threaded I/O Link): a bi-directional 16-bit data bus providing 533MB/sec of bandwidth. Moreover, the SiS645 is not limited to DDR memory; it will run with PC133 SDRAM, in addition to DDR333 and DDR266.
Unlike VIA, SiS has an official license from Intel to produce Pentium 4 chipsets. Therefore, the SiS645 is an obvious threat to the VIA P4X266. Speculation has it that Intel would like nothing more than to quash VIA's ambitions and is working with motherboard makers to ensure a smooth release (and rapid market adoption) for the SiS645. Are we talking Darth Intel here? Motherboard makers like Asus, Gigabyte, and MSI have signed on to produce boards based on the SiS645. A retail release is expected in September.