Issues with my wifi connection to Neduma R3

Zk_Trinita · 2026-07-15T11:23:31Z

Report: 5GHz channel width limited to 20MHz with MediaTek MT7921 Wi-Fi 6 client — Netduma R3

Summary

With a specific WiFi 6 client (MediaTek MT7921 chipset), the Netduma R3 never negotiates a channel width wider than 20MHz on 5GHz, regardless of the channel/bandwidth settings configured on the router. The same client, under identical signal quality, correctly negotiates full bandwidth (80MHz, 1201 Mbps link rate) with a different 5GHz access point in the same environment. Other client devices (e.g. a smartphone) reach normal speeds on the same Netduma R3, so this is not a general issue affecting all clients.

Devices involved

Router: Netduma R3, firmware v4.0.1147 (latest version available at time of testing)
Affected client: HP Victus by HP Gaming Laptop 16-r0xxx, MediaTek MT7921 Wi-Fi 6 802.11ax PCIe Adapter
Client driver: MediaTek Wireless LAN Driver v3.5.0.89 Rev.E (latest official HP release, freshly reinstalled during diagnosis)

Key data point: direct comparison at matched signal quality

Measured at the same time, same physical laptop position, via netsh wlan show interfaces:

Network	Channel	Resulting bandwidth	Signal	RSSI	Negotiated rate
ISP router (TIM, different 5GHz AP)	64	80MHz	78%	-62 dBm	1201 Mbps
Netduma R3	36	20MHz	78%	-63 dBm	286.8 Mbps

Signal and RSSI are essentially identical between the two networks (1 dB difference, negligible). The rate negotiated with the Netduma R3 is still a quarter of what's achieved with the other router, consistent with a drop from 80MHz to 20MHz channel width (2 spatial streams, MCS11 in both cases — only the channel width differs).

A second device (smartphone) connected to the same Netduma R3 on the same 5GHz band reaches real-world throughput up to ~600 Mbps, so the Netduma R3 is not globally stuck at 20MHz for all clients — only for this specific MediaTek MT7921 chipset.

Measured impact on real throughput

WiFi on Netduma R3: real throughput varying between ~130 and ~290 Mbps download depending on the test, with upload bufferbloat often elevated under load (300-450+ ms in several tests)
Ethernet cable on the same Netduma R3: 688 Mbps download / 952 Mbps upload, bufferbloat +27ms download / +31ms upload (excellent) — confirming the bottleneck is specific to the WiFi radio, not the rest of the router/QoS engine

Causes ruled out during diagnosis

Before isolating the issue described above, the following causes were tested and systematically ruled out, both router-side and client-side:

SmartBOOST: Gaming/Video & Streaming/VPN activity priorities lowered to minimum (1/1000) — no change in the declared bandwidth reservation or in real throughput
5GHz channel/bandwidth on the router: tested both on automatic and manually forced (channel 36, 80MHz) — no stable improvement
Client protocol (802.11ax vs forced 802.11ac): forcing 802.11ac made the negotiated rate worse, not better
Windows regional/regulatory domain: verified correct (Italy)
WiFi adapter power saving: already set to "Maximum Performance" on AC power
Bluetooth (antenna coexistence on the combo chip): fully disabled, no change
Congestion from neighboring WiFi networks: zero third-party networks visible in the scan
RSC (Receive Segment Coalescing): found globally disabled on Windows; re-enabling it made results noticeably worse
Windows QoS policies (Get-NetQosPolicy) and Group Policy bandwidth reservation: no policy present
Windows NetworkThrottlingIndex: modified/fully disabled, no effect
Packet loss: 0% over 50 consecutive pings to the router, 1-4ms RTT — base connection stable
CPU/driver load: no process or core saturated during speed tests
Network driver: full clean reinstall (uninstall + latest official driver from support.hp.com) — no change
Laptop BIOS reset to factory defaults: this did meaningfully improve the laptop's general WiFi performance (confirmed by the jump to 1201 Mbps with the other router), but did not resolve the specific limitation with the Netduma R3
Connection caching: Netduma R3 restart and "forget and reconnect" of the WiFi profile on Windows — no change in either case

Request

We would like to know whether this is a known interoperability issue between the Netduma R3's 5GHz radio and MediaTek MT7921 (WiFi 6) chipsets, and whether a firmware fix is planned. We're happy to provide further logs or repeat specific tests on request.