The WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) costs $0.0342/GB while the Seagate Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) costs $0.0360/GB. WD Ultrastar DC HC550 18TB Hard Drive 3.5' Internal 512MB SATA 7200 RPM 512E SE NP3 DC HC550 0F38459 (WUH721818ALE6L4) offers 5% 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 Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) — 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 Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) |
|---|---|---|
| Brand | Western Digital | Seagate |
| Capacity | 18TB | 20 TB |
| $/GB | $0.0342 | $0.0360 |
| Price | $615.95 | $719.99 |
| Retailer | Newegg | Amazon |
| 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 Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003)
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 $0.0342//GB compared to the Seagate Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) at $0.0360//GB — that's roughly 5% 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 $615.95 at Newegg, while the Seagate Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) starts at $719.99 at Amazon.
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 Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) 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 Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) 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 $0.0342//GB compared to Seagate Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) at $0.0360//GB. That is approximately 5% 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 $0.0342/GB ($615.95 for 18TB) at Newegg.
Where can I buy Seagate Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) for the cheapest price?
The cheapest price for the Seagate Skyhawk AI 20TB Video Internal Hard Drive HDD – 3.5 Inch SATA 6Gb/s 512MB Cache for DVR NVR Security Camera System with in-House Rescue Services (ST20000VE003) is $719.99 at Amazon, which works out to $0.0360/GB.