Ultrastar 7k4000 represents the sixth generation hgst 5 platter design which has been field proven by top server and storage oems and internet giants engineered for the highest quality the ultrastar 7k4000 is put through grueling design tests during development and must pass stringent ongoing reliability testing during manufacturing ultrastar 7k4000 delivers by reducing downtime eliminating service calls and minimizing tco operating at 7200 rpm ultrastar 7k4000 offers better overall pe