Silicon Integrated Systems

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Silicon Integrated Systems (SiS, Traditional Chinese: 矽統科技) is a company that manufactures, among other things, motherboard chipsets. The company was founded in 1987 in Hsinchu Science Park, Taiwan.

One of the most famous chipsets produced by SiS was the late 486-age chipset 496/497 which supported PCI bus among older ISA- and VLB-buses. This chipset with Intel 80486DX4, AMD 5x86 and Cyrix Cx5x86 processors had performance and compatibility comparable with early Pentiums, but prices incredibly lower and therefore very popular.

After this late success SiS continued positioning itself as a low-end chipsets producer. SiS developed the one-chip chipsets (with south and north bridges on one chip) SiS5596, SiS5598, SiS530 (for Pentium I), SiS620 (for Pentium II/III) with an integrated graphics core. The SiS 530 supports SDRAM, a bus frequency of up to 133 MHz, can have from 2 to 8M shared memory for an integrated AGP graphics (almost DirectX 7 compatible) controller, and USB. Motherboards on an SiS530 were positioned as cheap office platforms working together with AMD K6-2, and this gave performance comparable with Celerons around 400 MHz but priced sufficiently lower. However this chipset wasn't very popular due to low performance (especially graphics) and late appearance on the market.

In the late 1990s, SiS made the decision to invest in their own fab facilities. This placed severe financial strain on the company, and reduced the amount of money available for investing in new products, a mistake the management eventually recognised.

The SiS645 and SiS650 are very similar and contain integrated (chipsets) graphic cards. For a long period SiS branded integrated graphic cards and add-in boards, had a reputation for low performance, poor compatibility, and buggy drivers. However, post 2000, while still not offering feature rich chipsets, SiS solutions have remained cheap, but also delivered reasonable stability and performance.

SiS and ALi were the only two companies initially awarded licenses to produce third party chipsets for the Pentium 4, and the revenues from the 648 chipset, has played an important part in keeping SiS financially viable, most especially in the face of the success of VIA Technologies on the Athlon platform.

SiS created a multimedia chipset for the Xbox 360.[1]