The WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) costs $0.0372/GB while the Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) costs $0.0449/GB. WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) offers 17% better value per gigabyte as of August 2026. Both products are available on BuyPerUnit with prices from Amazon, Best Buy, and Newegg.
WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) vs Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) — Which Is Better Value?
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Specification Comparison
| Spec | WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) | Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) |
|---|---|---|
| Brand | Western Digital | Seagate |
| Capacity | 18TB | 20TB |
| $/GB | $0.0372 | $0.0449 |
| Price | $669.30 | $897.00 |
| Retailer | Newegg | Newegg |
| Category | Hard Drives (HDD) | Hard Drives (HDD) |
| Subcategory | hdd | hdd |
Price Across Retailers
WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4)
Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400)
Which Should You Buy?
Based on current pricing data, the WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) offers better value at $0.0372//GB compared to the Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) at $0.0449//GB — that's roughly 17% less per gigabyte.
The best deal for the WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) is $669.30 at Newegg, while the Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) starts at $897.00 at Newegg.
However, price per gigabyte isn't everything — consider factors like warranty, performance specs, brand reliability, and your specific capacity needs. Check each WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) and Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) product page for detailed specifications and price history.
Frequently Asked Questions
Is WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) or Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) a better deal?
As of August 2026, WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) offers better value at $0.0372//GB compared to Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) at $0.0449//GB. That is approximately 17% better value per gigabyte.
What is the price per GB of WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4)?
The WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) is currently priced at $0.0372/GB ($669.30 for 18TB) at Newegg.
Where can I buy Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) for the cheapest price?
The cheapest price for the Seagate Expansion 20TB External Hard Drive HDD - USB 3.0 with Rescue Data Recovery Services (STKP20000400) is $897.00 at Newegg, which works out to $0.0449/GB.