WD AV-GP drives are the cool, quiet & reliable choice for always-on 24/7 AV applications. They are designed for media center, media server, surveillance, digital signage & other AV systems requiring perfect audio & video, low heat, low power & long term reliability. 24x 7 reliability Near silent operation Silk Stream Technology Ultra-cool operation Low power consumption 1 million hours MTTF (MTBF) Performance Interface SATA 6.0 Gb/s Capacity 4TB RPM Intelli Power Cache 64MB 24x 7 reliability. These drives are designed to last in always-on, streaming digital audio/video environments such as PVRs, DVRs & surveillance video recorders. Reduced power consumption. With the combination of WD's Intelli Seek, Intelli Park, & Intelli Power technologies, WD has reduced power consumption by up to 40 percent compared to competitors' drives. Whisper quiet. Noise levels have been minimized to less than one sone – virtually below the threshold of human hearing. Compatible. Tested for compatibility in a broad range of AV products including set top boxes, DVD recorders, & mainstream surveillance systems. Silk Stream. Optimized for smooth, continuous digital video playback of up to twelve simultaneous HD streams. Silk Stream is compatible with the ATA streaming command set so CE customers can use standard streaming management & error recovery options. Intelli Seek. Calculates optimum seek speeds to lower power consumption, noise & vibration. Intelli Park. Delivers lower power consumption by automatically unloading the heads during idle to reduce aerodynamic drag. Preemptive Wear Leveling (PWL). The drive arm frequently sweeps across the disk to reduce uneven wear on the drive surface common to audio video streaming applications. Long-Term Reliability. These drives are designed to last in high temperature always-on streaming digital audio/video environments such as PVR/DVR, DVR recorders & surveillance video recorders. Ideal for: PVRs, DVRs, set-top boxes (STBs), & surveillance video recording.