Seagate
Seagate ST9640423AS 640GB 5400 RPM 16MB Cache SATA 2.5" laptop hard drive
A 640 GB 2.5-inch SATA laptop drive spinning at 5400 RPM with 16 MB cache and 9.5 mm height
- PackagingBare Drive
- InterfaceSATA
- Capacity640GB
- Cache16MB
- Average Seek Time11ms
- Average Write Time13ms
- 640GB capacity stores large media libraries and backups
- 5400 RPM spindle speed balances quiet operation with reliable throughput
- 16MB cache accelerates frequent read and write operations
- 5 inch 9.5mm form factor fits standard laptop drive bays
- SATA interface enables direct replacement in compatible notebooks
Capacity and Form Factor
The Seagate ST9640423AS is a 640GB 2.5-inch internal hard drive designed for laptop upgrades or replacements. It operates at 5400 RPM with a 16MB cache and connects via a standard SATA interface.
Suitable Uses and Limitations
This drive suits users restoring older notebooks or needing affordable bulk storage for documents and media where high speed is not critical. It is not suited for buyers who require faster boot times, quicker application loading, or lower latency than a 5400 RPM mechanical drive can provide.
Deciding Specification
The 5400 RPM spindle speed is the single figure that determines whether this drive meets your performance expectations. Average seek time is 11ms, average write time is 13ms, and average latency is 5.6ms.
Highlights
- 640GB capacity stores large media libraries and backups
- 5400 RPM spindle speed balances quiet operation with reliable throughput
- 16MB cache accelerates frequent read and write operations
- 5 inch 9.5mm form factor fits standard laptop drive bays
- SATA interface enables direct replacement in compatible notebooks
Specifications
| Brand | Seagate |
|---|---|
| Series | Momentus |
| Model | ST9640423AS |
| Packaging | Bare Drive |
| Interface | SATA |
| Capacity | 640GB |
| Cache | 16MB |
| Average Seek Time | 11ms |
| Average Write Time | 13ms |
| Average Latency | 5.6ms |
| RPM | 5400 RPM |
| Form Factor | 2.5" |
| Height (maximum) | 9.5mm |
| Width (maximum) | 69.85mm |
| Length (maximum) | 100.35mm |
| Shipping weight | 0.45 kg |
| Package size | 152 × 102 × 51 mm |
Questions about this item
What is the first limit reached during sustained use with the 5400 RPM spindle?
Sustained throughput is limited by the 5400 RPM spindle and 16MB cache, which together cap sequential transfer rates below faster drives.
How much noise and heat does the drive produce when running all day?
The 5400 RPM motor and 9.5mm height typically yield low acoustic output and modest heat, suitable for continuous laptop operation.
What existing laptop interface is required for the SATA connection to work?
The notebook must provide a standard 2.5-inch SATA bay with a 7-pin data and 15-pin power connector.
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