Seagate
Seagate Momentus 5400.3 ST9120822AS 120GB 5400 RPM 8MB SATA 1.5Gb/s 2.5" laptop hard drive
A 120 GB 2.5 inch laptop hard drive with 5400 RPM and 8 MB cache over SATA 1.5Gb/s
- PackagingBare Drive
- InterfaceSATA 1.5Gb/s
- Capacity120GB
- Cache8MB
- Average Latency5.6ms
- RPM5400 RPM
- 120 GB capacity stores your operating system and files
- 5400 RPM spindle speed delivers quiet everyday performance
- 8 MB cache buffers frequent reads for smoother response
- SATA 1.5 Gb/s interface connects to most legacy laptops
- Low power consumption extends battery life on the move
120 GB 2.5-inch SATA laptop drive
The Seagate Momentus 5400.3 ST9120822AS is a 120 GB internal hard drive built for 2.5-inch laptop bays. It connects through a SATA 1.5Gb/s interface and spins at 5400 RPM with an 8 MB cache. The bare-drive packaging suits repair technicians and system integrators who install the unit directly. Low power consumption helps extend battery life in portable machines.
Replaces slower or smaller 2.5-inch SATA drives
This drive upgrades laptops that originally shipped with lower-capacity or lower-cache SATA 1.5Gb/s mechanisms. The jump is worthwhile when the existing drive has become a capacity bottleneck or when its cache is smaller than 8 MB. Average latency of 5.6 ms reflects the 5400 RPM spindle speed, so the improvement is most noticeable in sequential file access rather than random I/O. Buyers who need higher spindle speeds or a faster SATA revision should look elsewhere.
Steady throughput under sustained load
During prolonged read or write sessions the 5400 RPM spindle and 8 MB cache deliver consistent throughput without the burst-to-sustained drop seen in higher-RPM drives. Low power consumption keeps thermal output modest, allowing the drive to maintain its transfer rate inside cramped laptop chassis. The SATA 1.5Gb/s link caps maximum sequential speed, so sustained performance plateaus at the interface limit rather than the mechanical limit. This behaviour suits archival storage and media playback where predictability matters more than peak speed.
Highlights
- 120 GB capacity stores your operating system and files
- 5400 RPM spindle speed delivers quiet everyday performance
- 8 MB cache buffers frequent reads for smoother response
- SATA 1.5 Gb/s interface connects to most legacy laptops
- Low power consumption extends battery life on the move
Specifications
| Brand | Seagate |
|---|---|
| Series | Momentus 5400.3 |
| Model | ST9120822AS |
| Packaging | Bare Drive |
| Interface | SATA 1.5Gb/s |
| Capacity | 120GB |
| Cache | 8MB |
| Average Latency | 5.6ms |
| RPM | 5400 RPM |
| Features | Low power consumption |
| Form Factor | 2.5" |
| Shipping weight | 0.09 kg |
| Package size | 102 × 64 × 13 mm |
Questions about this item
Will the 2.5" form factor fit my laptop's SATA drive bay?
The drive uses the standard 2.5" form factor with a SATA 1.5Gb/s interface, matching most laptop internal bays that accept 2.5" SATA drives.
What is the correct way to install this bare SATA drive without damaging the connector?
Align the SATA data and power connectors with the laptop's port, press straight in until seated, then secure with the caddy screws; forcing it at an angle bends the fragile connector pins.
When should I expect to replace this 5400 RPM mechanical drive?
Mechanical drives with 5400 RPM spindle speeds typically show wear after several years of daily use; monitor SMART reallocated-sector counts and replace once they rise steadily.
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