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FireCuda 520 vs. WD_Black SN850

The FireCuda 520 and WD_Black SN850 are both PCIe 4.0 x4 solid state drives. So, what are the main differences between these two products?

You can find out in this comparison guide for the Seagate and Western Digital SSDs.

Quick Summary

When compared to the Seagate FireCuda 520, the Western Digital WD_Black SN850 is substantially faster at maximum sequential reading, maximum sequential writing and maximum random reading.

The WD_Black SN850 is also a little bit faster than the FireCuda 520 at maximum random writing.

On the other hand, the FireCuda 520 has much better endurance than the SN850 as you will be able to write approximately three times as many data.

If you are interested, you can purchase either of the aforementioned solid state drives on Amazon with the following links:

You can also check out how the FireCuda 520 compares to the Samsung 980 Pro with this guide. Furthermore, you can also take a look at how the SN850 stacks up against the 980 Pro with this page.

FireCuda 520 vs. WD_Black SN850 Comparison Chart

You can find a comparison table between the FireCuda 520 and SN850 below.

 Seagate FireCuda 520 Solid State DriveWestern Digital WD_Black SN850 Solid State Drive
Capacity Options500GB

1TB

2TB
500GB

1TB

2TB
Heat Sink Option?NoYes
Model Numbers500GB FireCuda 520: ZP500GM30002

1TB FireCuda 520: ZP1000GM30002

2TB FireCuda 520: ZP2000GM30002
500GB WD_Black SN850: WDS500G1X0E-00AFY0

1TB WD_Black SN850: WDS100T1X0E-00AFY0

2TB WD_Black SN850: WDS200T1X0E-00AFY0

500GB WD_Black SN850 with Built-In Heatsink: WDS500G1XHE-00AFY0

1TB WD_Black SN850 with Built-In Heatsink: WDS100T1XHE-00AFY0

2TB WD_Black SN850 with Built-In Heatsink: WDS200T1XHE-00AFY0
InterfacePCIe 4.0 x4PCIe 4.0 x4
NAND3D TLCBiCS4 96L TLC
Maximum Sequential Read Speed500GB FireCuda 520: Up to 5000 MB per second

1TB FireCuda 520: Up to 5000 MB per second

2TB FireCuda 520: Up to 5000 MB per second
500GB WD_Black SN850: Up to 7000 MB per second

1TB WD_Black SN850: Up to 7000 MB per second

2TB WD_Black SN850: Up to 7000 MB per second
Maximum Sequential Write Speed500GB FireCuda 520: Up to 2500 MB per second

1TB FireCuda 520: Up to 4400 MB per second

2TB FireCuda 520: Up to 4400 MB per second
500GB WD_Black SN850: Up to 4100 MB per second

1TB WD_Black SN850: Up to 5300 MB per second

2TB WD_Black SN850: Up to 5100 MB per second
Maximum Random Read Speed500GB FireCuda 520: Up to 430K IOPS

1TB FireCuda 520: Up to 760K IOPS

2TB FireCuda 520: Up to 750K IOPS
500GB WD_Black SN850: Up to 810K IOPS

1TB WD_Black SN850: Up to 1000K IOPS

2TB WD_Black SN850: Up to 1000K IOPS
Maximum Random Write Speed500GB FireCuda 520: Up to 630K IOPS

1TB FireCuda 520: Up to 700K IOPS

2TB FireCuda 520: Up to 700K IOPS
500GB WD_Black SN850: Up to 680K IOPS

1TB WD_Black SN850: Up to 720K IOPS

2TB WD_Black SN850: Up to 710K IOPS
Endurance500GB FireCuda 520: 850 TBW

1TB FireCuda 520: 1800 TBW

2TB FireCuda 520: 3600 TBW
500GB WD_Black SN850: 300 TBW

1TB WD_Black SN850: 600 TBW

2TB WD_Black SN850: 1200 TBW
Operating Temperature Range32°F to 158°F (or 0°C to 70°C)32°F to 158°F (or 0°C to 70°C)
Non-Operating Temperature Range-40°F to 185°F (or -40°C to 85°C)-67°F to 185°F (or -55°C to 85°C
Warranty5-year limited warranty5-year limited warranty
PricingCheck price on Amazon.Check price on Amazon.

Capacity Options

Both the Seagate and Western Digital solid state drives in this versus guide offer the following capacity options:

  • 500GB
  • 1TB
  • 2TB

Heat Sink Option

Unlike the FireCuda 520, the WD_Black SN850 can be purcahsed with an optional built-in heat sink.

Model Numbers

You can take a look at the model numbers for all currently available options for both SSDs below:

  • 500GB FireCuda 520: ZP500GM30002
  • 1TB FireCuda 520: ZP1000GM30002
  • 2TB FireCuda 520: ZP2000GM30002
  • 500GB WD_Black SN850: WDS500G1X0E-00AFY0
  • 1TB WD_Black SN850: WDS100T1X0E-00AFY0
  • 2TB WD_Black SN850: WDS200T1X0E-00AFY0
  • 500GB WD_Black SN850 with Built-In Heatsink: WDS500G1XHE-00AFY0
  • 1TB WD_Black SN850 with Built-In Heatsink: WDS100T1XHE-00AFY0
  • 2TB WD_Black SN850 with Built-In Heatsink: WDS200T1XHE-00AFY0

Interface

The Seagate FireCuda 520 and Western Digital WD_Black SN850 utilize the PCIe 4.0 x4 interface.

NAND

For NAND, the FireCuda 520 uses 3D TLC while the WD_Black SN850 uses BiCS4 96L TLC.

Maximum Sequential Read Speed

The WD_Black SN850 is quite a bit better than the FireCuda 520 when it comes to maximum sequential reading.

All capacities of the SN850 are 2000 MB faster, or 40% faster, than the capacities of the FireCuda 520.

You can find the maximum sequential read speed specifications below:

  • 500GB FireCuda 520: Up to 5000 MB per second
  • 1TB FireCuda 520: Up to 5000 MB per second
  • 2TB FireCuda 520: Up to 5000 MB per second
  • 500GB WD_Black SN850: Up to 7000 MB per second
  • 1TB WD_Black SN850: Up to 7000 MB per second
  • 2TB WD_Black SN850: Up to 7000 MB per second

Maximum Sequential Write Speed

The WD_Black SN850 also has a major advantage over the FireCuda 520 at maximum sequential writing as well.

When comparing the same capacity options, the 500GB SN850 is 1600 MB per second faster, or 64% faster, than the 500GB FireCuda 520.

The 1TB SN850 is also 900 MB per second faster, or 20.45% faster, than the 1TB FireCuda 520.

Finally, the 2TB SN850 is 700 MB per second faster, or 15.91% faster, than the 2TB FireCuda 520.

You can check out the maximum sequential write speeds below:

  • 500GB FireCuda 520: Up to 2500 MB per second
  • 1TB FireCuda 520: Up to 4400 MB per second
  • 2TB FireCuda 520: Up to 4400 MB per second
  • 500GB WD_Black SN850: Up to 4100 MB per second
  • 1TB WD_Black SN850: Up to 5300 MB per second
  • 2TB WD_Black SN850: Up to 5100 MB per second

Maximum Random Read Speed

Furthermore, the WD_Black SN850 also beats out the FireCuda 520 at maximum random reading.

The 500GB WD_Black SN850 is 380K IOPS faster, or 88.37% faster, than the 500GB FireCuda 520.

The 1TB WD_Black SN850 is also 240K IOPS faster, or 31.58% faster, than the 1TB FireCuda 520.

Last but not least, the 2TB WD_Black SN850 is 250K IOPS faster, or 33.33% faster, than the 2TB FireCuda 520.

You can take a look at the maximum random read speed specs below:

  • 500GB FireCuda 520: Up to 430K IOPS
  • 1TB FireCuda 520: Up to 760K IOPS
  • 2TB FireCuda 520: Up to 750K IOPS
  • 500GB WD_Black SN850: Up to 810K IOPS
  • 1TB WD_Black SN850: Up to 1000K IOPS
  • 2TB WD_Black SN850: Up to 1000K IOPS

Maximum Random Write Speed

While the WD_Black SN850 is also faster at maximum random writing when compared to the FireCuda 520, the differences aren’t as big as the other speed categories.

For random writes, the 500GB WD_Black SN850 is 50K IOPS faster, or 7.94% faster, than the 500GB FireCuda 520.

Moreover, the 1TB WD_Black SN850 is 20K IOPS faster, or 2.86% faster, than the 1TB FireCuda 520.

Finally, the 2TB WD_Black SN850 is 10K IOPS faster, or 1.43% faster, than the 2TB FireCuda 520.

You can check out the random writing speeds below:

  • 500GB FireCuda 520: Up to 630K IOPS
  • 1TB FireCuda 520: Up to 700K IOPS
  • 2TB FireCuda 520: Up to 700K IOPS
  • 500GB WD_Black SN850: Up to 680K IOPS
  • 1TB WD_Black SN850: Up to 720K IOPS
  • 2TB WD_Black SN850: Up to 710K IOPS

Endurance

When it comes to endurance, which measures how much data can be written on a solid state drive, the Seagate FireCuda 520 has a major advantage over the Western Digital WD_Black SN850.

The 500GB FireCuda 520 is capable of writing 550 TB more data, or 183.33% more, than the 500GB WD_Black SN850.

You can also write 1200 TB more data, or 200% more, with the 1TB FireCuda 520 than the 1TB WD_Black SN850.

Finally, the 2TB FireCuda 520 is capable of writing 2400 TB more data, or 200% more, than the 2TB WD_Black SN850.

You can find the TerabBytes Written (TBW) specs below:

  • 500GB FireCuda 520: 850 TBW
  • 1TB FireCuda 520: 1800 TBW
  • 2TB FireCuda 520: 3600 TBW
  • 500GB WD_Black SN850: 300 TBW
  • 1TB WD_Black SN850: 600 TBW
  • 2TB WD_Black SN850: 1200 TBW

Operating Temperature Range

The two solid state drives in this comparison guide have identical recommended operating temperature range of 32°F to 158°F (or 0°C to 70°C).

Non-Operating Temperature Range

For non-operation, the SN850 can tolerate colder temperatures when compared to the FireCuda 520.

You can take a look at the non-operating temperature ranges below:

  • FireCuda 520: -40°F to 185°F (or -40°C to 85°C)
  • WD_Black SN850: -67°F to 185°F (or -55°C to 85°C

Warranty

The Seagate FireCuda 520 Solid State Drive and Western Digital WD_Black SN850 Solid State Drive each comes with a 5-year limited warranty.

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