Dell 4TB 3.5-inch 7.2K SAS 12Gbps Hard Drive — YXG4K

Here is a 4TB hard drive for 3.5-inch SAS bays, supplied under Dell part number YXG4K with a Seagate mechanism inside, maker model ST4000NM0025. It spins at 7.2K rpm and connects at 12Gbps.

Hot-plug bays let a failed member of a redundant array be replaced without powering the server down. Parity RAID levels set aside space for redundancy, so size arrays on usable capacity rather than the sum of the drives. Dell-labelled drives are intended for PowerEdge servers and PowerVault arrays with 3.5-inch SAS bays. Keeping a spare drive per array shortens the time an array runs degraded after a failure. It needs a SAS controller or HBA, and it negotiates down to 6Gbps on older SAS controllers. Capacity-class disks like this are the usual building block for backup repositories, video archives and large file shares. The part number YXG4K is the reliable reference when checking this drive against your system.

Sold as certified refurbished, the drive passes inspection and a bench test, and has its storage wiped, in Johannesburg before release.