Quick Summary (TL;DR):
The QNAP TS-464 and TS-664 are almost the same NAS platform with a different number of SATA bays. Both current models use the Intel Celeron N5095 with four cores/four threads, support up to 16GB DDR4, include two M.2 2280 PCIe Gen3 x1 slots, dual 2.5GbE, one PCIe Gen3 x2 expansion slot and HDMI 2.1 up to 4K60. Both run QTS and can switch to QuTS hero on supported current software. The TS-664’s real advantage is its six drive bays instead of four. That makes RAID 6 substantially more capacity-efficient, gives you more room to expand before replacing existing disks, and can make large media/backup pools cheaper per usable terabyte. The TS-464 remains the better fit when four bays already meet your five-year storage estimate: it is smaller, uses fewer drives, has lower total drive-replacement cost and runs the same CPU, containers, VMs and media workloads. Buy the TS-664 for capacity growth—not because you expect more CPU, RAM, network or Plex performance.
QNAP TS-464 vs TS-664 at a Glance
| Feature | TS-464 | TS-664 |
|---|---|---|
| CPU | Intel Celeron N5095 | Intel Celeron N5095 |
| Cores / threads | 4 / 4 | 4 / 4 |
| Max burst | 2.9GHz | 2.9GHz |
| Graphics | Intel UHD Graphics | Intel UHD Graphics |
| RAM | 8GB DDR4 current model; max 16GB | 8GB DDR4 current model; max 16GB |
| SATA bays | 4 | 6 |
| M.2 | 2 × PCIe Gen3 x1 | 2 × PCIe Gen3 x1 |
| Networking | 2 × 2.5GbE | 2 × 2.5GbE |
| PCIe | 1 × Gen3 x2 | 1 × Gen3 x2 |
| HDMI | HDMI 2.1, up to 4K60 | HDMI 2.1, up to 4K60 |
| QTS / QuTS hero | Yes | Yes |
| Typical operating power | 40.536W | 44.02W |
| Dimensions | 165 × 170 × 226.5mm | 165 × 235 × 226.5mm |
| Best fit | General four-bay home server | Large/growing storage pool |
The Hardware Platform Is Essentially the Same
QNAP’s own current comparison page shows that the two models share almost every core hardware specification.
- Intel Celeron N5095.
- 4 cores / 4 threads.
- Up to 2.9GHz burst.
- Intel UHD Graphics.
- 8GB DDR4 on current 8G models.
- Maximum 16GB memory.
- Two M.2 2280 PCIe Gen3 x1 slots.
- Dual 2.5GbE.
- PCIe Gen3 x2 expansion.
- Two USB 3.2 Gen2 10Gbps Type-A ports.
- HDMI 2.1 up to 4096 × 2160 at 60Hz.
That means this is not a “cheap CPU vs fast CPU” comparison. It is a storage-capacity decision.
For our previous cross-brand four-bay comparison, see UGREEN DXP4800 Plus vs QNAP TS-464.
Four Bays vs Six Bays Changes RAID Economics
With conventional RAID, parity consumes a fixed number of drives.
For equal-size disks:
RAID 5 usable
≈ (number of drives - 1) × drive size
RAID 6 usable
≈ (number of drives - 2) × drive sizeThat means two extra bays are especially valuable with RAID 6 because the two parity drives represent a smaller share of the total array.
RAID 5 Capacity with 12TB Drives
| NAS | Drive set | Raw capacity | Approx. RAID 5 usable before overhead |
|---|---|---|---|
| TS-464 | 4 × 12TB | 48TB | 36TB |
| TS-664 | 6 × 12TB | 72TB | 60TB |
The TS-664 adds 24TB of usable RAID 5 capacity when the two extra 12TB drives are installed.
RAID 6 Is the Stronger Six-Bay Argument
With RAID 6, both arrays sacrifice two drives to parity.
| NAS | Drive set | Raw capacity | Approx. RAID 6 usable before overhead |
|---|---|---|---|
| TS-464 | 4 × 12TB | 48TB | 24TB |
| TS-664 | 6 × 12TB | 72TB | 48TB |
On four bays, RAID 6 uses half the raw drive capacity for parity. On six bays, two-thirds of the raw capacity remains available before filesystem overhead.
This is why a six-bay enclosure makes much more sense when you specifically want two-drive fault tolerance.
RAID 6 with 16TB Drives
| NAS | Drive set | Approx. RAID 6 usable |
|---|---|---|
| TS-464 | 4 × 16TB | 32TB |
| TS-664 | 6 × 16TB | 64TB |
The six-bay system effectively doubles protected usable capacity in this specific RAID 6 example.
RAID 6 with 20TB Drives
| NAS | Drive set | Approx. RAID 6 usable |
|---|---|---|
| TS-464 | 4 × 20TB | 40TB |
| TS-664 | 6 × 20TB | 80TB |
If your realistic five-year target is 60–80TB of usable protected storage, the TS-664 can reach it with mainstream high-capacity drives while a four-bay system becomes restrictive much sooner.
QNAP Officially Positions the TS-664 for Much Larger Pools
QNAP’s current product pages illustrate the difference using 24TB hard drives:
- TS-464: QNAP illustrates up to 72TB storage using four 24TB drives in RAID 5, plus M.2 SSD cache.
- TS-664: QNAP illustrates up to 120TB storage using six 24TB drives in RAID 5, plus M.2 SSD cache.
These are QNAP’s example usable-storage configurations, not raw chassis limits for every future drive capacity.
The TS-664 Also Opens More RAID Layout Options
Both systems support the common RAID layouts required by most home users.
With six bays, however, QNAP’s current QuTS hero software also exposes layouts such as RAID 50 that are not practical on a four-bay chassis.
RAID 50 stripes across RAID 5 groups. It is more relevant to specialised performance/capacity designs than ordinary family backups, but it is another example of how more bays increase architectural choice.
The Extra Bays Can Delay Replacing Existing Drives
This is often more important than maximum headline capacity.
Imagine a TS-464 with four 12TB drives is becoming full. Depending on the RAID layout, increasing capacity may eventually require replacing working disks with larger models.
With a six-bay chassis, you have two additional internal positions that can participate in supported storage-pool expansion or new pool designs.
QNAP supports online RAID capacity expansion and online RAID level migration in its storage-management stack, but always verify the exact source/target RAID migration path before buying around a future plan.
Two Extra Bays Are Not Free Capacity
The TS-664 only gives you more capacity after you buy more hard drives.
A realistic cost comparison includes:
- NAS enclosure.
- Four versus six HDDs.
- Future replacement drives.
- A spare drive if you keep one on hand.
- UPS capacity.
- Backup storage large enough to protect the array.
Two additional 16TB or 20TB NAS drives can cost more than the difference between the two enclosures.
Our capacity-cost guide covers this separately: 8TB vs 12TB vs 16TB vs 20TB NAS Drives: Cost per Usable Terabyte.
CPU Performance Is a Tie
Both current NAS systems use the same Intel Celeron N5095.
- 4 cores.
- 4 threads.
- Up to 2.9GHz burst.
- Intel UHD Graphics.
- AES-NI encryption support.
- Hardware-accelerated transcoding support in QNAP’s platform.
The TS-664 does not process Docker containers, databases or Plex streams faster simply because the chassis contains two more bays.
If the N5095 is too slow for your workload, you need a different performance tier—not the TS-664.
RAM Is Also a Tie
QNAP currently lists both 8G models with:
- 8GB DDR4 installed.
- Two SO-DIMM slots.
- 16GB maximum official memory.
Six drive bays do not give the TS-664 a larger VM or Docker memory budget.
If you need 32GB or 64GB RAM for a large home-lab stack, neither model is the ideal platform.
Docker and Virtual Machines Are Effectively the Same
Both run the same QNAP software ecosystem, including:
- Container Station.
- Virtualization Station.
- Linux Station.
- Virtual Switch networking.
- Storage & Snapshots.
- Hybrid Backup Sync.
The TS-664 can provide more bulk storage to those workloads, but not more CPU or RAM.
Plex and Jellyfin Performance Is Also a Tie
Both use the same Intel graphics architecture in the N5095 and QNAP lists hardware-accelerated transcoding support on both models.
For Plex/Jellyfin:
- Direct Play performance is effectively a storage/network workload.
- Hardware transcoding capability comes from the same CPU/iGPU platform.
- Six bays let you store a larger media library.
- They do not create more transcoding engines.
Choose the TS-664 for media capacity, not for media compute.
Networking Is Identical
Both provide two 2.5GbE interfaces.
QNAP also gives both one PCIe Gen3 x2 slot, allowing supported network expansion such as 5GbE or 10GbE adapters.
QNAP’s own current product material promotes dual-port 10GbE PCIe upgrades on both models.
The TS-664 therefore does not have a networking advantage just because a six-drive array may be capable of more aggregate disk throughput.
Two M.2 Slots on Both
Both models have two M.2 2280 PCIe Gen3 x1 slots.
They can be used for supported SSD cache/storage workflows in QTS or QuTS hero.
If two slots are insufficient, both models can use supported QM2 PCIe expansion cards to add more M.2 SSDs, depending on the exact card and configuration.
Again, the six-bay model does not add M.2 resources.
QTS vs QuTS hero Is the Same Choice on Both
Both use QTS by default and QNAP currently allows supported systems to switch to QuTS hero from QTS 5.2.1 onward.
QuTS hero uses ZFS and adds features centred on data integrity, WORM protection, compression and other storage functionality.
The TS-664’s additional bays can make some ZFS/RAID layouts more useful, but the operating-system option itself is not exclusive to it.
The TS-664 Is Physically Wider
QNAP lists:
- TS-464: 165 × 170 × 226.5mm.
- TS-664: 165 × 235 × 226.5mm.
Height and depth are the same, but the six-bay unit is about 65mm wider.
That matters if the NAS will sit on a narrow shelf or inside a cabinet.
Cooling Changes with the Larger Chassis
The TS-464 uses one 120mm fan.
The TS-664 uses two 90mm fans.
Do not conclude from fan diameter alone that one is quieter. Acoustic behaviour depends on fan speed, installed hard drives, vibration and chassis resonance.
Power Consumption Is Closer Than You Might Expect
QNAP’s current fully-populated test figures are:
- TS-464: 40.536W typical operating, 21.618W disk standby.
- TS-664: 44.02W typical operating, 23.22W disk standby.
The difference in QNAP’s test is relatively small despite two additional drives, but these are vendor test conditions rather than universal wall-power measurements.
Real consumption depends on the exact HDDs, SSDs, PCIe cards and workload.
The TS-664 Uses a Larger Power Supply
QNAP specifies:
- TS-464: 90W external adapter.
- TS-664: 120W external adapter.
The larger supply provides the headroom required for six drives and the wider chassis configuration. It does not mean the TS-664 continuously consumes 120W.
Six Bays Can Make a Better Backup Repository
For a large household or home lab, the TS-664 can be a more practical backup target because it can provide:
- More usable capacity in RAID 6.
- More room for snapshots.
- More space for workstation backups.
- More space for Proxmox/VM backups.
- Longer retention before pruning old versions.
But a larger backup repository also creates a larger problem when the NAS itself must be backed up.
Plan the Backup of the NAS Before Filling Six Bays
A 60–100TB primary pool cannot be sensibly protected by one small USB disk.
You may need:
- A second NAS.
- Multiple external drives.
- Selective cloud backup.
- Tiered backup where irreplaceable data receives stronger protection than replaceable media.
RAID 6 protects against drive failure. It still does not replace an independent backup.
When the TS-464 Is the Better Buy
- Four drives already provide enough five-year capacity.
- You want RAID 5 rather than RAID 6.
- Your usable requirement is below roughly 30–40TB with current drive sizes.
- You want the smaller chassis.
- You want to minimise initial and replacement drive cost.
- You need the same N5095 CPU, Plex capability, Docker and VMs.
- You plan to use PCIe for 10GbE or QM2 expansion rather than more SATA disks.
When the TS-664 Is Worth It
- You already expect more than four disks’ worth of long-term storage.
- You prefer RAID 6 with better capacity efficiency.
- Your media library is growing quickly.
- You keep long backup/snapshot retention periods.
- You want 50–80TB+ usable protected storage without buying the largest available disks.
- You want more room to expand before replacing working drives.
- You are interested in six-drive layouts such as RAID 50 under supported QuTS hero configurations.
When Neither Is the Right Upgrade
If your problem is CPU or RAM, moving from TS-464 to TS-664 changes nothing.
Consider a different NAS tier if you need:
- More than 16GB RAM.
- A significantly faster processor.
- More hardware transcoding capacity.
- Built-in 10GbE without using PCIe.
- Several PCIe expansion slots.
The extra two bays only solve a storage-capacity problem.
A Practical Buying Matrix
| Your priority | Better fit | Reason |
|---|---|---|
| Compact four-bay home server | TS-464 | Same compute/platform in a smaller chassis |
| RAID 5 up to moderate capacity | TS-464 | Four bays are often enough |
| RAID 6 with 50TB+ target | TS-664 | Six bays dramatically improve usable capacity |
| Plex/Jellyfin compute | Tie | Same N5095 and Intel graphics |
| Docker / VMs | Tie | Same CPU and RAM ceiling |
| 2.5GbE / PCIe / M.2 | Tie | Core I/O platform is the same |
| Large media library | TS-664 | Two more SATA bays |
| Lowest complete drive cost | TS-464 | Fewer disks to buy and replace |
QNAP TS-464 vs TS-664: The Bottom Line
The TS-464 is the better value if four bays are enough. You get the same N5095, same 16GB memory ceiling, same Intel graphics, same dual 2.5GbE, same two M.2 slots, same PCIe Gen3 x2 expansion and the same QTS/QuTS hero ecosystem in a smaller enclosure.
The TS-664 earns its premium when you genuinely need more storage. Six bays make RAID 6 far more efficient, support larger pools with mainstream drive sizes and give you room to grow before replacing the drives you already own.
Do not buy the TS-664 because “six is better than four”. Buy it when your five-year capacity plan proves that the extra two drive positions will be used.
The useful rule is simple: if the bottleneck is storage, choose the TS-664; if the bottleneck is CPU or RAM, choose neither and move to a higher performance tier.
Continue the NAS Buying Series
- 2-Bay vs 4-Bay vs 6-Bay NAS: Which Size Should You Buy?
- UGREEN DXP4800 Plus vs QNAP TS-464
- 8TB vs 12TB vs 16TB vs 20TB NAS Drives: Cost per Usable Terabyte