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Deal.ai › Seagate
Seagate
Seagate 7200.3 ST3400820SCE 400 GB 3.5 Internal Hard Drive - SATA/300 - 7200 rpm - 8 MB Buffer

Seagate 7200.3 ST3400820SCE 400 GB 3.5 Internal Hard Drive - SATA/300 - 7200 rpm - 8 MB Buffer

Best price now

$492.14at Tech Network Supply LLCChecked Nov 12

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Price facts

  • Last seen at $492.14 at Tech Network Supply LLC on Nov 12.

Our take on the Seagate 7200.3 ST3400820SCE 400 GB 3.5 Internal Hard Drive - SATA/300 - 7200 rpm - 8 MB Buffer

The Seagate 7200.3 ST3400820SCE is a 3.5-inch internal desktop hard drive with 400 GB of capacity, a 7200 rpm spindle and a 6 Gb/s SATA interface. It is a legacy part: the 7200.3 line dates from the late 2000s, and 8 MB of cache is small next to the 32–64 MB buffers on later drives. It suits someone replacing a failed drive in an old desktop or NAS, or reading data off a retired system, not a new build. Modern 3.5-inch drives offer far more capacity and speed per unit, so it makes sense only where the old interface and form factor are the point.

Best forReplacing a failed drive in an older desktop PCReviving a legacy SATA system or enclosureReading data from a retired machineBudget storage for a non-critical old build
Pros
  • Standard 3.5-inch SATA form factor fits most desktop bays
  • 7200 rpm spindle for desktop-class sequential speed
  • 400 GB is ample for an older OS and basic files
  • Simple plug-in SATA/300 connection, no adapter needed
Cons
  • 8 MB cache is small by later standards
  • Legacy model with no current manufacturer support
  • Slower and smaller than any current 3.5-inch drive
  • Old stock carries higher failure risk than new drives

Seagate 7200.3 ST3400820SCE 400 GB 3.5 Internal Hard Drive - SATA/300 - 7200 rpm - 8 MB Buffer prices at every store

  • Tech Network Supply LLCNew

    In stockReturn policy

    $492.14Checked Nov 12
    Visit Tech Network Supply LLC

About the Seagate 7200.3 ST3400820SCE 400 GB 3.5 Internal Hard Drive - SATA/300 - 7200 rpm - 8 MB Buffer

This is the Seagate 7200.3 ST3400820SCE, a 400 GB internal hard drive in the 3.5-inch size. It connects through a SATA/300 interface.

The drive spins at 7200 rpm and has an 8 MB buffer.

Brand
Seagate
Series
7200.3
Model
ST3400820SCE
Capacity
400 GB
Form factor
3.5 inch, internal
Interface
SATA/300
Speed
7200 rpm
Buffer
8 MB

Questions and answers

Is this drive worth buying today?
Only for a specific job: replacing a failed drive in an old desktop or reading data from a legacy system. For new builds, current 3.5-inch drives are faster, larger and better supported.
Will it work in a modern PC?
It uses a standard SATA connection, so it will connect to most modern motherboards. Capacity and speed are the limits, not compatibility.
What is the cache size and why does it matter?
It has an 8 MB buffer. That is small compared with later drives, which carry 32 MB or more, and it affects burst performance on small random reads.
Is 400 GB enough?
For an older operating system and documents, yes. For a modern game or media library, no; current drives start at several times this capacity.
Can I use it in a NAS or RAID array?
It is a desktop-class drive, not a NAS drive built for continuous multi-drive use. It can work in a light RAID setup, but reliability under 24/7 load is not its design goal.
Where is the Seagate 7200.3 ST3400820SCE 400 GB 3.5 Internal Hard Drive - SATA/300 - 7200 rpm - 8 MB Buffer cheapest?
At Tech Network Supply LLC, for $492.14, as of our latest check.

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