Review on HGST Ultrastar 7K4000 4TB 64MB Cache 7200RPM SATA 6.0Gb/s 3.5inch Internal Hard Drive - Ideal Storage Solution for NAS, Desktop PC/Mac, Surveillance, CCTV DVR - 5 Year Warranty (Renewed) by Charles Chambers

I installed the replacement and did a 12 hour test and it works fine with no major issues. Upgrade to 4 stars. it would be 5 but for DOA one first. The replacement process was quick and painless. The sand arrived in 2 days. Original rating. After connecting to my computer, my computer would not turn on. When I checked to see if the drive was spinning, the board was so hot it hurt. You can also see some discoloration on the board, so I don't know how it passed internal testing. A replacement is on the way and will change my rating pending the outcome.