Teardown of a 10G SFP+ Module Reveals Heat, Chips, and a Hidden Compatibility MCU
A teardown of 10Gbit SFP+ adapters shows they run hot (idle around 40°C) and can dissipate up to about 2.5W. The module houses a Marvell Alaska X 88X3310/40P PHY with a metal heatsink attached to the enclosure and an 8051-based MCU that flags the module as a 30 m multimode fiber type for compatibility. Newer Wiitek-branded modules use a newer chipset and run cooler. The takeaway is to ensure adequate airflow or use the appropriate fiber type to avoid heat-induced frame drops; older modules may discolor and stress thermally, suggesting single-mode fiber as a cooler, practical alternative.