J-403TG © 199? Jetway
The Jetway J-403TG is a versatile 486-class motherboard featuring a Socket 3 design that supports Intel, AMD, and Cyrix 486 processors (DX, DX2, DX4, and 5x86). It is built around the UMC UM8881/UM8886 Green chipset, which was the standard-bearer for reliable 486-to-PCI bridge implementations. Unlike the VLB-centric boards, the J-403TG focuses on the PCI bus, offering 3 PCI slots and 4 ISA slots. It supports up to 64 MB of RAM through 72-pin SIMM sockets and typically features a 256 KB L2 cache (often soldered on-board or via a COAST module). Its BIOS is known for having a clean, intuitive setup interface, which was a hallmark of Jetway’s mid-90s push for "user-friendly" system building.
PCI Maturity: The J-403TG represents the era where PCI was finally "mature." By this model's release, the early PCI timing issues that plagued the first generation of 486-PCI boards were mostly solved. This board was often the safe choice for builders who wanted the speed of a PCI graphics card (like the S3 Trio64) without the instability of early 486-PCI designs.
The "TG" Suffix: In Jetway's nomenclature, the "TG" often referred to their "Turbo Green" series. This highlighted their focus on the power-saving features that were rapidly becoming mandatory for corporate office machines in 1995.