Advanced Integration Research (AIR) 486US Chipset UMC UM82C480 (386/486 PC Chip Set) with Socket 3 (PGA237) / WTL4167 (PGA144), FSB speeds 20/25/33/50 MHz, Baby AT form factor (330 mm x 218 mm), 64‑256 KB cache, max 32 MB RAM (30‑pin SIMM), 7×16‑bit ISA slots, 1×8‑bit ISA slot, AT power connector, AT keyboard port.