HDD vs SSD for Home Servers
Quick Answer
Use SSDs for your OS, Docker volumes, and databases. Use HDDs for bulk storage (media, backups, photos). This is the right answer for 95% of home server setups. SSDs are 10-50x faster for random I/O (which Docker and databases need) but cost 5-8x more per TB (which bulk storage can’t justify).
The Numbers
| Metric | 3.5” HDD (NAS) | 2.5” SATA SSD | M.2 NVMe SSD |
|---|---|---|---|
| Sequential read | 150-250 MB/s | 500-550 MB/s | 2,000-7,000 MB/s |
| Sequential write | 150-200 MB/s | 500-530 MB/s | 1,500-5,000 MB/s |
| Random read (IOPS) | 100-200 | 50,000-90,000 | 200,000-1,000,000 |
| Random write (IOPS) | 100-200 | 50,000-80,000 | 100,000-500,000 |
| Price per TB | $15-20 | $60-80 | $60-100 |
| Power (idle) | 4-6W | 0.5-1W | 0.5-2W |
| Power (active) | 6-10W | 2-3W | 3-8W |
| Noise | 25-35 dB | Silent | Silent |
| Lifespan (typical) | 3-5 years | 5-10 years | 5-10 years |
| Vibration | Yes (affects multi-bay setups) | None | None |
The critical difference is random I/O. An NVMe SSD handles 500,000+ random IOPS. An HDD manages ~150. That’s a 3,000x difference. For Docker container startup, database queries, and Nextcloud file operations, random I/O performance determines how responsive your server feels.
When to Use HDDs
Bulk Media Storage
Movies, TV shows, music, audiobooks — large files accessed sequentially. A modern HDD’s 200 MB/s sequential read is more than enough to stream 4K video (which needs ~25 MB/s). Even streaming to 5 clients simultaneously only needs 125 MB/s — well within a single HDD’s capability.
Cost to store 20 TB of media:
- HDD: 2x 12 TB in RAID 1 = ~$380
- SSD: 2x 12 TB SATA SSD = ~$1,600+
- NVMe: Not available in 12 TB at consumer prices
HDDs win by 4x on cost for bulk storage.
NAS Primary Storage
For a NAS storing files, photos, and backups alongside media, HDDs are the practical choice. SHR/RAID 5 across 4 HDDs gives you reasonable random I/O performance through striping, and the cost per TB makes large arrays affordable.
Cold Backups
Backup drives that are powered on periodically for backup jobs and then powered off. HDDs are fine for this — the writes are sequential, and cost per TB matters more than speed.
When to Use SSDs
OS and Boot Drive
Always use an SSD for your operating system. Docker images, container layers, and system operations all involve random I/O. An HDD boot drive makes everything feel sluggish.
Minimum recommendation: 256 GB NVMe SSD for the OS and Docker. ~$20-25.
Docker Volumes and Databases
Containers like PostgreSQL, MariaDB, Nextcloud, and Immich generate heavy random I/O. Database queries perform 100-1,000x faster on an SSD.
The difference in practice:
- Nextcloud page load on HDD: 2-5 seconds
- Nextcloud page load on NVMe SSD: 0.2-0.5 seconds
NAS Cache
Most NAS setups benefit from an NVMe cache:
- Synology: NVMe read/write cache accelerates frequently-accessed files
- TrueNAS: SLOG (write) and L2ARC (read) on NVMe dramatically improve random I/O
- Unraid: Cache pool absorbs writes, mover transfers to HDD array in background
A 500 GB NVMe cache SSD costs ~$35 and transforms how responsive a HDD-based NAS feels.
All-Flash NAS (When Budget Allows)
If your total storage needs are under 4-8 TB, an all-SSD NAS is increasingly viable:
- 4x 2 TB SATA SSD: ~$320 total
- Completely silent, no vibration
- Dramatically faster for all workloads
- Lower power consumption (~4W total vs ~24W for 4 HDDs)
The break-even point: if your storage needs exceed 8 TB, HDDs become the clear cost winner.
The Hybrid Approach (Recommended)
Most home servers should use both:
| Storage Tier | Drive Type | Use For | Size |
|---|---|---|---|
| Tier 1: System | NVMe SSD | OS, Docker, databases | 256 GB - 1 TB |
| Tier 2: Fast storage | NVMe SSD (NAS cache) | Frequently accessed files, app data | 500 GB - 2 TB |
| Tier 3: Bulk storage | HDD (NAS array) | Media, photos, backups, archives | 8-100+ TB |
Mini PC + NAS Setup
- Mini PC: NVMe SSD for OS and Docker (built-in)
- NAS: HDDs for bulk storage, NVMe for cache
- Connection: Gigabit or 2.5 GbE Ethernet between them
- Mount: NFS or SMB shares from NAS on mini PC
This separates compute (fast) from storage (big) — each device does what it’s best at.
Single Device Setup
If running everything on one device (DIY NAS with TrueNAS or Unraid):
- Boot: Dedicated NVMe SSD (128-256 GB) for OS
- Cache: Second NVMe SSD (500 GB - 1 TB) for ZFS SLOG/L2ARC or Unraid cache
- Array: HDDs for bulk storage
Power Consumption Comparison
Over a year of 24/7 operation at $0.12/kWh:
| Configuration | Power | Annual Cost |
|---|---|---|
| 4x 3.5” HDD (7200 RPM) | ~24W | $25 |
| 4x 2.5” SATA SSD | ~4W | $4 |
| 4x 3.5” HDD + 1x NVMe cache | ~26W | $27 |
| 1x NVMe (OS) + 4x HDD | ~26W | $27 |
SSDs save ~$5/drive/year in electricity. Over 5 years with 4 drives, that’s $100 in savings — meaningful but not enough to offset the HDD vs SSD price difference for large capacities.
Noise
HDDs produce 25-35 dB of noise from spinning platters and head movement. SSDs are silent.
If your server is in a living space, bedroom, or home office, noise matters. Options:
- Use SSDs for everything (expensive for bulk storage)
- Put the NAS in a closet, basement, or utility room
- Use 5400 RPM drives (quieter than 7200 RPM) — see WD Red Plus
- Enable HDD hibernation for infrequently-accessed drives
FAQ
Can I use desktop SSDs in a NAS?
Yes, SATA SSDs work in any NAS that accepts 2.5” drives (with a 3.5” adapter if needed). For NAS caching, use NVMe SSDs designed for write-heavy workloads. Avoid QLC SSDs (Samsung 870 QVO, Crucial BX500) for cache/database use — their write endurance is lower than TLC alternatives.
Will an SSD wear out from self-hosting?
Unlikely. A modern 1 TB TLC SSD is rated for 600 TBW (terabytes written). At 50 GB/day of writes (heavy database + Docker use), it lasts 32 years. Normal self-hosting writes far less than this.
Should I use NVMe or SATA SSD for my NAS cache?
NVMe. It’s 4-10x faster than SATA SSD for random I/O, and the price difference is minimal. A 500 GB NVMe costs ~$35 vs ~$40 for a 500 GB SATA SSD.
Are enterprise SSDs worth it for home use?
No. Consumer NVMe SSDs have more than enough endurance for home server workloads. Enterprise SSDs (Intel Optane, Samsung PM series) are designed for 24/7 datacenter writes at 10-100x the volume of a home server.
Related
Get self-hosting tips in your inbox
New guides, comparisons, and setup tutorials — delivered weekly. No spam.