I had the 1st generation WD MYBOOKLIVE 2TB and the HDD temp was always at 5X °C (sometimes over 60°C) . Yes, the use of an external fan is a must! Anyway, won't consider any fanless 3.5" NAS or HDD enclosure. That kind of design is a total failure. Fanless design might only be good for SSD (absolutely not for 3.5" HDD).