204-pin memory modules are primarily used in DDR3 SO-DIMM configurations, which are commonly found in laptops, mini PCs, and all-in-one systems. These smaller modules offer excellent power efficiency and high performance in mobile computing devices. With a reduced pin count compared to 288-pin desktop modules, 204-pin modules are designed to meet the needs of portable and energy-efficient systems, delivering reliable memory performance in compact spaces without compromising on speed.