486 motherboard using the ALi 1487/1489 chipset © 199? Unknown
This chipset is a two-chip solution (often referred to as the M1487 system controller and M1489 data buffer/PCI interface). It was highly regarded by motherboard manufacturers for its stability and superior performance in handling concurrent PCI and ISA/VLB bus transactions. It provided the logic necessary to move the 486 platform into the modern PCI era.
Processor Support: Designed for 486DX, DX2, DX4, and 5x86 processors (Socket 3).
Bus Support: Full PCI 2.0/2.1 compliant. Unlike many hybrid chipsets of the time, the ALi 1489 was purpose-built for the PCI local bus, allowing for significantly higher throughput for graphics and SCSI cards.
Memory: Supported high-density configurations, typically up to 128MB of 72-pin SIMM RAM, with advanced support for EDO (Extended Data Out) DRAM, which gave it a slight performance edge over older Fast-Page Mode (FPM) boards.
Cache: Integrated support for Write-Back L2 cache, usually offering better performance metrics than equivalent SiS or UMC chipsets in professional benchmarks of the mid-90s.
The "ALi Speed" Reputation: The M1489 chipset was often praised in late-90s hardware reviews for its "no-nonsense" reliability. While it didn't have the "overclocking" fame of some high-end enthusiast boards, it was the backbone of many professional-grade 486 workstations that needed to run 24/7 without bus contention issues.