HP 768424-001 rear system fan is a replacement fan for restoring airflow in supported HP desktop systems. HP's service guide identifies 768424-001 as the fan, and the distributor listing names it as a rear system fan.
The guide shows the fan positioned beneath the heat sink, connected to the system board at CHFAN and held by four Torx screws. The listing names HP EliteDesk 705 G1 and 800 G1, and ProDesk 400 G1 and 600 G1 Desktop Mini PCs as compatible systems.