WD Purple Surveillance HDD – 4TB 5400 RPM, SATA 6 Gb/s, 256MB Cache, AllFrame 4K, 3.5" CMR – WD44PURZ

The Western Digital Purple 4TB (Model: WD44PURZ) is a surveillance-optimized 3.5-inch hard drive engineered for 24/7 DVR and NVR environments. Utilizing a SATA 6 Gb/s interface, a 5400 RPM spindle speed, and an expansive 256MB cache buffer, this CMR drive delivers sustained, high-bandwidth write performance. Rated for intensive workloads up to 180TB/year, it natively supports concurrent data streams from up to 64 HD cameras. The drive integrates proprietary AllFrame 4K technology via ATA streaming commands to mitigate critical frame loss, while onboard IntelliSeek dynamically optimizes seek speeds to minimize rotational vibration, power consumption, and mechanical wear.