How to choose a NAS hard drive
Choose an exact drive model supported by your enclosure, then compare the array's usable capacity and cost. A low price per TB alone does not establish that the drive's recording technology, interface or warranty suits the NAS.
Identify the exact drive
Seagate's recording-technology table lists IronWolf and IronWolf Pro under CMR. Its Exos range includes different technologies, so a family name alone is insufficient. Check the exact model and capacity against the manufacturer's table and your NAS support list.
Price the usable array
Mirroring and parity use capacity. Four equal 8 TB drives in RAID 6 provide an arithmetic 16 TB before filesystem and system overhead: (4 − 2) × 8 TB. The RAID calculator shows the formula and lets you enter the current per-drive price.
Keep condition and warranty in the comparison
A refurbished listing needs its own warranty and return terms. Seagate's factory-recertified warranty statement does not establish what an independent seller offers. Compare new and refurbished prices as separate choices.
Dated manufacturer and application information
Seagate. Seagate describes its factory-recertified products as carrying a six-month warranty. This does not establish the warranty of a separate marketplace seller.
Seagate. SMR overlaps recording tracks. Seagate lists recording technology by product family and capacity; IronWolf and IronWolf Pro are listed under CMR, while the Exos range includes different recording technologies.
Synology. Standard RAID capacity depends on the smallest member drive and how much capacity mirroring or parity uses.
Compare prices and specifications
NAS drive listingsRAID capacity and cost calculatorCMR vs SMR