In How-To Geek’s account, Jorge A. Aguilar describes connecting his NAS to the first available router port, then discovering that the working connection was limiting performance. The useful lesson is not that everyone needs 10GbE. It is that checking the connection you already own should come before buying an upgrade.
Identical connectors do not guarantee identical speeds
Some NAS systems combine Ethernet ports with different capabilities. Synology’s performance guide, for example, describes products equipped with both 1GbE and 10GbE connections. That does not mean every NAS has mixed-speed ports: the exact model’s specifications remain the authority.
Three numbers matter:
- Port capability: the speeds the hardware supports.
- Negotiated link speed: the rate at which the connection is currently operating.
- File-transfer throughput: how quickly the application actually moves data.
These are not interchangeable. Synology explicitly distinguishes checking the reported network speed from investigating storage, CPU utilization, and other causes of slow transfers. QNAP similarly recommends testing network throughput independently of file-sharing performance.
A faster NAS connection also cannot remove a slower connection elsewhere in the path. The switch or router must support the intended rate, and the client connection needs checking too. Think of it as inspecting the whole road, not merely widening the driveway.
Check your NAS connection before moving cables
Start with access to the NAS management interface and the model documentation for your NAS and switch. Record the existing connection and its reported speed before changing anything; that gives you a useful before-and-after comparison.
1. Read the current NAS link speed
On Synology DSM 7 and legacy DSM versions covered by its troubleshooting guidance, open:
Control Panel > Network > Network Interface
Inspect the active interface’s network status. Synology lists 1,000 Mbps as the expected rate for a 1GbE connection and 10,000 Mbps for a 10GbE connection. A lower reading warrants checking the connected network device and cable.
On QNAP QTS or QuTS hero, QNAP documents this route:
Control Panel > Network & Virtual Switch > Interfaces
Check the Speed and Duplex values for the physical adapter. These are vendor-specific paths, not universal NAS menu names.
2. Check the Windows side
On a Windows 11 PC, open Windows PowerShell and run this read-only adapter query:
Get-NetAdapter
Microsoft documents Get-NetAdapter as the cmdlet for retrieving basic network-adapter properties. Inspect the active wired adapter’s status and link-speed output; do not mistake a disconnected adapter or virtual interface for the Ethernet connection carrying your NAS traffic. This checks the PC’s connection, not the entire route to storage.
3. Match the ports, then retest
Compare the reported rates with the capabilities documented for the exact NAS and switch ports. If the switch supports port-status reporting, check that end too. Synology specifically recommends confirming that the router or switch supports the intended connection speed.
If the connection is unexpectedly slow, try a known-good, appropriately rated Ethernet cable. Change one item at a time and check the negotiated speed again. Synology includes cable condition and cable substitution in its slow-transfer troubleshooting procedure. Success at this stage means the connection reports the expected rate—not that every file copy reaches it.
Cable advice needs a distance caveat
Cat5e can support 2.5GbE on equipment designed for it; Cisco documents that capability on its multigigabit switch ports. For 10GbE, however, “Cat6 works” is incomplete advice. Cable manufacturer ICC explains that Cat6 operation between 37 and 55 meters depends on the alien-crosstalk environment. Cisco documents Cat6A support for 10GbE runs up to 100 meters on the relevant fixed ports. Check both the installation and the equipment requirements rather than treating the category label as a universal guarantee.
An unexpected 100 Mbps connection is a reason to investigate cabling, not proof of a particular broken wire. Cisco’s cabling documentation distinguishes the four-pair requirement for 1000BASE-T from the two-pair wiring that can support 100BASE-TX. Cable substitution is a sensible first diagnostic; a specific fault still needs evidence.
Faster links and faster file copies are different victories
Once the expected link rate appears, repeat a large-file transfer. If results remain disappointing, compare file-copy performance with a network-throughput test such as iperf3. QNAP recommends this separation: normal network-test results alongside slow file transfers point the investigation toward file services or system performance rather than immediately blaming Ethernet.
Nor should two connected cables automatically be counted as twice the speed. Synology distinguishes link aggregation, which benefits aggregate traffic, from SMB Multichannel, which can improve a supported single client’s SMB throughput.
Microsoft explains that SMB Multichannel can establish multiple connections for one SMB session and use bandwidth across suitable adapters. Compatibility still matters: Synology’s published requirements include supported models, DSM and SMB Service versions, and appropriate adapters; its implementation does not allow SMB Multichannel and Link Aggregation concurrently.
Finally, security settings deserve diagnosis rather than reflexive disabling. Synology acknowledges that SMB encryption or signing can reduce performance, but that does not establish either as the cause of a particular slowdown.
The practical order is simple: verify port capabilities, inspect actual link rates, test the cable and network path, then investigate storage and SMB performance. A cable move may solve the problem. When it does not, those checks still prevent an expensive upgrade from becoming a very fast distraction.