How to choose a storage drive

1. Check what connects to your system

Find the PC, motherboard or enclosure model and read its storage specifications. Distinguish 2.5-inch SATA, M.2 SATA, M.2 NVMe, 3.5-inch SATA, SAS and USB. An M.2 slot does not automatically support both SATA and NVMe. Check supported card length, available lanes, any shared-port restrictions and heatsink clearance. For a NAS, look up the complete drive model in the manufacturer's compatibility guidance, including the relevant firmware or operating-system version.

Source: Kingston: SSD interfaces, slots and compatibility

2. Calculate capacity from your files and growth

Measure the data you have, estimate growth over your intended upgrade period and reserve room for the system and working files. As an illustration, 600GB today plus 300GB of planned additions totals 900GB before that reserve; compare suitable 1TB and 2TB options instead of buying by a universal rule. For backups, include retained versions as well as the current files. For a NAS mirror, two equal drives provide one drive's nominal capacity. Filesystem overhead and system reservations reduce available space further.

Source: Synology: capacity and drive requirements by RAID type

3. Match the workload to the exact model

Check a game's published storage requirements before using an HDD for an active installation. For editing or repeated large writes, compare sustained performance and SSD endurance at the exact capacity. For a NAS HDD, verify CMR or SMR from the manufacturer's model documentation and follow the NAS vendor's requirements; a family name alone is not enough. Treat an unknown specification as unknown. Also consider where the drive will run: an enterprise HDD's noise, power and cooling needs may matter in a bedroom NAS.

4. Compare the whole purchase, then price per TB

Shortlist compatible models first. Compare the same capacity and condition, then check total cost as well as dollars per TB. A larger drive can have the lower unit cost while still exceeding your budget. Add the enclosure, required controller, backup storage and any shipping or tax to your plan. With multiple drives, compare the full set and usable capacity after redundancy. The cheapest offer is useful only if you can use it.

5. Check the seller and plan for a failure

Confirm the exact model, condition, seller, return period and who provides the warranty. A manufacturer's model-level warranty specification does not by itself prove coverage for a particular used or imported unit. Read workload and endurance ratings as product limits under stated conditions, not predictions of lifespan. New and used drives can fail; RAID is not an independent backup. Keep another recoverable copy of important data and test that you can restore it. A used drive may fit a budget, but its price must justify the seller terms, uncertain history and replacement effort.

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Frequently Asked Questions

Sources

• Kingston: SATA and M.2 SSD compatibility
• Synology: drive compatibility
• Synology: RAID types and capacity