Western Digital WD40PURZ 4TB 5400 RPM 64MB Cache 3.5" SATA internal hard drive

WD Purple 4TB surveillance drive

The WD Purple WD40PURZ is a 4TB 3.5-inch internal hard drive engineered for 24/7 video surveillance workloads. It connects via SATA 6.0Gb/s and is tuned for write-intensive, low bit-rate, high stream-count applications typical of NVR environments. The drive is tested for compatibility across a wide range of security systems. It is not suited for general desktop storage or workloads that demand low-latency random access.

Thermals, noise and power

Designed to withstand elevated heat fluctuations and equipment vibrations inside always-on NVR enclosures. The 5400 RPM spindle speed and surveillance-class firmware help manage thermal output during continuous write operations. Exclusive AllFrame technology reduces frame loss and improves video playback smoothness. Tarnish-resistant components add durability in harsh operating conditions.

180TB annual workload rating

The drive supports up to 180TB per year workload rate, a figure that determines whether it matches the write volume of your surveillance deployment. It also supports installations of more than 8 bays and includes TLER and ATA streaming support. Buyers needing higher capacity can choose models up to 18TB. Builders requiring a drive optimised for random read performance or desktop operating systems should select a different product class.