Seagate ST31000340SV 1TB 7200 RPM 32MB SATA 3.0Gb/s 3.5" internal hard drive

1TB SV35.3 surveillance drive

The Seagate ST31000340SV is a 3.5 inch internal hard drive built for continuous video recording. It spins at 7200 RPM with a 32MB cache and connects through a SATA 3.0Gb/s interface. The SV35.3 series targets 24x7 operation with a rated MTBF above one million hours and an annualised failure rate below one percent.

Best for multi-stream recording

This drive suits installers and system integrators deploying DVR or NVR appliances that write several camera streams simultaneously. The firmware is tuned for sustained sequential writes rather than random access, so it is not a fit for boot drives, general-purpose storage or workloads that demand low latency random IOPS.

Capacity and headroom

At 1TB the drive holds weeks of footage from a modest camera count at typical bitrates. The 32MB buffer and 7200 RPM spindle absorb bursty write peaks from multiple streams, but the single SATA 3.0Gb/s link and mechanical latency of 4.16ms become the bottleneck once aggregate throughput approaches the interface ceiling.