Best Hardware for TrueNAS in 2026
Quick Recommendation
For TrueNAS SCALE (Linux-based, recommended): Used Dell OptiPlex 7060 Tower ($150) with an i5-8500, 32 GB ECC DDR4 ($60 used), and an LSI 9207-8i HBA ($30). Add 4x 4 TB Seagate IronWolf drives ($260) in a RAIDZ1 vdev. Total: ~$500 for 12 TB usable ZFS storage with Docker support.
For TrueNAS CORE (FreeBSD-based): Same hardware works, but Docker isn’t available. Use Jails instead. CORE is the legacy path — new users should choose SCALE.
The non-negotiable: If you’re running ZFS on TrueNAS, get ECC RAM. ZFS stores data checksums in RAM during writes. A bit flip in RAM can cause ZFS to write corrupt data and then validate its own corruption. ECC costs $10–$20 more than non-ECC and eliminates this risk entirely.
What TrueNAS Needs (ZFS Drives Everything)
TrueNAS is a ZFS-based storage system. ZFS’s requirements determine your hardware choices.
RAM: 1 GB per TB of Storage (Minimum)
ZFS uses RAM aggressively for its ARC (Adaptive Replacement Cache). The rule of thumb:
| Storage | Minimum RAM | Recommended RAM |
|---|---|---|
| 4–8 TB | 8 GB | 16 GB |
| 8–16 TB | 16 GB | 32 GB |
| 16–32 TB | 32 GB | 64 GB |
| 32+ TB | 64 GB | 128 GB |
More RAM = faster reads because more data lives in cache. ZFS without adequate RAM performs poorly — it constantly reads from disk instead of cache.
ECC RAM is strongly recommended. Not technically required, but ZFS’s data integrity guarantees assume reliable RAM. A single bit flip during a scrub or resilver can cause silent data corruption that ZFS can’t detect. ECC prevents this.
For the ECC debate, see ECC vs Non-ECC RAM.
CPU: Moderate Power, AES-NI Required
ZFS operations are mildly CPU-intensive:
- Checksumming every data block (fletcher4 by default — lightweight)
- Compression (LZ4 by default — very fast, barely touches CPU)
- Encryption (AES-256-GCM if enabled — requires AES-NI instructions)
- Scrubs/resilvers read every block and verify checksums
A 4-core i3 handles up to 20 TB of storage easily. You need more cores only if running Docker containers or VMs alongside the NAS.
AES-NI is mandatory if you plan to use ZFS native encryption. Every Intel CPU since Westmere (2010) and every AMD CPU since Bulldozer (2011) has AES-NI. Not a practical concern with modern hardware.
Storage Controller: HBA in IT Mode
ZFS needs direct access to individual drives — no hardware RAID controller in between.
Best option: LSI/Broadcom HBA in IT (Initiator Target) mode:
| Controller | Ports | Price (Used) | Notes |
|---|---|---|---|
| LSI 9207-8i | 8 SAS/SATA | $25–$40 | Most popular, well-supported |
| Dell H310 Mini Mono | 8 SAS/SATA | $15–$25 | Flash to IT mode — cheapest option |
| LSI 9300-8i | 8 SAS/SATA | $40–$60 | PCIe 3.0, newer firmware |
| Broadcom 9500-8i | 8 SAS/SATA | $80–$120 | PCIe 4.0, NVMe support |
Do NOT use a hardware RAID controller. RAID controllers abstract drive access. ZFS needs raw drive access for its checksumming and redundancy to work correctly. A hardware RAID controller beneath ZFS defeats ZFS’s entire purpose.
Motherboard SATA ports work for small arrays (4–6 drives). Use an HBA when you need more ports.
Boot Drive
TrueNAS boots from a separate drive that is NOT part of the ZFS storage pool. Options:
- USB flash drive — works but slow and wears out. TrueNAS SCALE writes more to boot media than CORE, so USB is less ideal for SCALE.
- Small SATA SSD (120–256 GB) — recommended. Cheap, reliable, fast boot.
- NVMe SSD — overkill for boot, but fine if your board has a spare M.2 slot.
- Mirror two boot drives — TrueNAS supports mirrored boot. Protects against boot drive failure. Worth doing.
SLOG and L2ARC (Optional)
SLOG (Separate Log): A fast NVMe drive for the ZFS Intent Log (ZIL). Improves synchronous write performance. Useful for iSCSI, NFS with sync=always, or VM storage. Not needed for typical NAS workloads (SMB file sharing is asynchronous by default).
L2ARC: Second-level read cache on an SSD. Extends ARC capacity beyond RAM. Only useful when your working set exceeds available RAM. For most home servers, adding more RAM is more cost-effective than adding L2ARC.
If you’re a beginner: Skip both. They add complexity and cost with minimal benefit for typical home NAS use. Add them later if you identify specific performance bottlenecks.
Recommended Builds
Budget Build ($350–$450)
File server with Docker support. 12 TB usable (RAIDZ1).
| Component | Recommendation | Price |
|---|---|---|
| System | Used Dell OptiPlex 7060 Tower (i5-8500, 8 GB) | $120 |
| RAM upgrade | 32 GB DDR4 ECC UDIMM (2x16, used) | $60 |
| Boot drive | 120 GB SATA SSD | $15 |
| HBA | Dell H310 Mini Mono (IT mode) | $20 |
| SAS cables | 2x SFF-8087 to 4x SATA | $15 |
| Storage | 4x 4 TB Seagate IronWolf (RAIDZ1) | $260 |
| Total | ~$490 |
Note: The OptiPlex 7060 Tower (not Micro/SFF) has room for multiple 3.5” drives. Check that the specific configuration has enough internal drive bays.
Mid-Range Build ($600–$800)
NAS + Docker + Plex. 24 TB usable (RAIDZ1 or RAIDZ2).
| Component | Recommendation | Price |
|---|---|---|
| CPU | Intel i5-12400 | $130 |
| Motherboard | ASRock B660M Pro RS (4 SATA, M.2, ECC support via i5) | $90 |
| RAM | 32 GB DDR4 ECC UDIMM (2x16) | $70 |
| Boot drive | 256 GB NVMe SSD | $25 |
| Case | Fractal Design Node 304 (6x 3.5”) | $80 |
| PSU | Corsair CX450M | $45 |
| Storage | 4x 8 TB Seagate IronWolf | $480 |
| Total | ~$920 |
Usable storage: RAIDZ1 = 24 TB. RAIDZ2 = 16 TB (better protection).
Important: Intel 12th gen i5 (non-K) supports ECC on specific motherboards. Verify ECC support in the motherboard manual. ASRock B660 boards generally support ECC.
High-End Build ($1,000–$1,500)
Full NAS + VMs + heavy Docker. 48+ TB usable.
| Component | Recommendation | Price |
|---|---|---|
| CPU | AMD Ryzen 7 5700X | $150 |
| Motherboard | ASRock B550M Pro4 (6 SATA, ECC support) | $90 |
| RAM | 64 GB DDR4 ECC UDIMM (2x32) | $150 |
| Boot drives | 2x 256 GB SATA SSD (mirrored) | $40 |
| SLOG | Intel Optane M10 16 GB (used) | $15 |
| HBA | LSI 9207-8i (IT mode) | $35 |
| Case | Fractal Design Define 7 (14x 3.5” bays) | $150 |
| PSU | Corsair RM750 (80+ Gold) | $90 |
| Storage | 6x 12 TB Seagate Exos (RAIDZ2) | $780 |
| Total | ~$1,500 |
Usable storage: RAIDZ2 = 48 TB with dual parity protection.
ZFS Pool Layout Recommendations
| Drives | Best Layout | Usable Capacity | Fault Tolerance |
|---|---|---|---|
| 2 | Mirror | 50% | 1 drive |
| 3 | RAIDZ1 | 67% | 1 drive |
| 4 | RAIDZ1 | 75% | 1 drive |
| 4 | 2x Mirror (striped) | 50% | 1 per mirror |
| 5 | RAIDZ2 | 60% | 2 drives |
| 6 | RAIDZ2 | 67% | 2 drives |
| 6 | 3x Mirror (striped) | 50% | 1 per mirror |
| 8+ | RAIDZ2 or 2x RAIDZ1 | Varies | 2 drives |
For home use: RAIDZ1 with 3–5 drives is the sweet spot. RAIDZ2 if you have 5+ drives and want extra safety.
Never use RAIDZ1 with large drives (8+ TB). Resilver times with large drives can exceed 24 hours, during which a second failure destroys the pool. Use RAIDZ2 or mirrors for drives 8 TB and larger.
For ZFS hardware requirements, see ZFS Hardware Requirements.
TrueNAS SCALE vs CORE
| Feature | SCALE (Linux) | CORE (FreeBSD) |
|---|---|---|
| Docker/Kubernetes | Yes (native) | No (Jails only) |
| VM support | Yes (KVM) | Yes (bhyve) |
| ZFS support | Full | Full |
| Active development | Primary focus | Maintenance mode |
| App ecosystem | Larger (Docker Hub) | Smaller (iXsystems apps) |
Choose SCALE for new installations. It’s the future of TrueNAS, has Docker support, and runs on the Linux kernel (better driver support).
Choose CORE only if you have an existing CORE installation you don’t want to migrate, or if you need FreeBSD-specific features (Jails with full FreeBSD userland).
FAQ
Do I really need ECC RAM?
For ZFS: strongly recommended. ZFS’s scrub process trusts RAM contents to verify disk contents. A single bit flip in RAM during a scrub can cause ZFS to “correct” good data with bad data. ECC costs $10–$20 more than non-ECC and eliminates this risk.
For non-ZFS NAS operating systems (Unraid, OMV): ECC is optional. These systems don’t rely on RAM-based checksumming.
Can I use a mini PC for TrueNAS?
Technically yes, but most mini PCs max out at 16 GB non-ECC RAM and have no SATA ports beyond the boot drive. You’d need USB-attached storage, which ZFS doesn’t handle well (USB disconnects cause pool issues). Use a desktop or tower build for TrueNAS.
How much power does a TrueNAS server draw?
Depends on drives:
- System (CPU + board + boot SSD): 20–40W
- Each spinning 3.5” HDD: 6–8W
- Each 2.5” SSD: 1–2W
A 4-drive NAS: 45–70W. A 6-drive NAS: 55–90W. Annual cost at $0.12/kWh: $47–$95.
Can I expand storage later?
You can add new vdevs (groups of drives) to a pool at any time. You cannot add drives to an existing RAIDZ vdev (this is a ZFS limitation — though RAIDZ expansion is coming in OpenZFS). Plan your initial vdev layout with expansion in mind.
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