486 motherboard using the SiS 85C471/85C407 chipset © 199? Unknown
The 85C471 was the "System Controller," while the 85C407 served as the "Data Buffer." This pair was the "gold standard" for 486 motherboards in the mid-1990s. Unlike the earlier, more complex OPTi or VLSI boards, the SiS 471 was celebrated for its high degree of integration and its advanced support for Write-Back (WB) L2 cache, which was critical for achieving maximum performance from the 486's internal cache.
Processor Support: Designed for 486SX, DX, DX2, DX4, and the AMD 5x86.
Bus Architecture: Primarily built for the VLB (VESA Local Bus) and ISA era. It was one of the most reliable implementations of the VLB interface, which made it a favorite for users who needed high-speed VLB graphics (like the Tseng Labs ET4000/W32) and high-speed disk controllers.
Memory: Typically supported up to 128MB or 256MB of RAM using 72-pin SIMMs, featuring excellent support for page-mode and EDO DRAM.
Cache: Specifically optimized for 256KB to 512KB of Write-Back (WB) cache, which provided the "punch" that defined the 486 experience.
The "471" Reputation: The SiS 85C471 is arguably the most famous 486 chipset. It was reliable, easy to configure, and was used by virtually every major motherboard manufacturer (including ASUS, Gigabyte, and ECS). If you have a vintage 486 board in your collection, there is a very high statistical probability it is based on this chipset.