I recently moved and switched internet providers. My self-built Windows 11 PC connected normally to the new modem/router for a few days, but now the Wi‑Fi connection is extremely unstable. The PC detects the wireless network, connects briefly, and then loses internet access almost immediately. Occasionally it works for a few minutes, but most of the time it drops right away. Other devices on the same network work normally.
I've already forgotten and re-added the network, restarted the computer repeatedly, performed a full network reset, renewed the IP address, flushed the network cache, reset the adapter, and removed the wireless device through Device Manager before restarting. I also tried registry changes from a Windows support guide, but nothing helped. I'd really like to avoid reinstalling Windows.
The wireless adapter is a MediaTek Wi‑Fi 6 MT7921. Could this be a driver or compatibility problem? I'm also wondering whether the router's distance, antenna connections, or wireless mode might be responsible. I need a stable connection for classes soon.
3 Answers
The provider’s modem/router combination could be part of the problem. Some of those gateways don’t work well with certain Wi‑Fi adapters or newer security and channel settings. If possible, test the PC close to the router first. If it works reliably nearby, distance or interference is involved; if it still fails beside the router, it points more toward the adapter, its driver, or compatibility with the gateway. Replacing the gateway with a separate router also fixed this kind of issue for some people.
The MT7921 has a history of connection and driver problems, especially with newer Wi‑Fi modes. First, make sure both external antennas are firmly attached and positioned upright. In the adapter’s properties, try disabling Wi‑Fi 6/802.11ax or setting the preferred wireless mode to 802.11n/ac temporarily. You can also test the router on a 2.4 GHz network instead of 5 GHz. If that stabilizes things, the problem is probably compatibility or driver-related rather than Windows itself.
I tried changing the wireless mode and a few other suggested settings, but the connection still keeps dropping.
Download the latest MT7921 driver from your motherboard or system manufacturer’s support page rather than relying only on Windows Update. Check the exact motherboard model and Windows 11 version before installing it. In Device Manager, also disable the adapter’s power-saving option under the Power Management tab, and set its roaming aggressiveness and transmit power to higher values if those options are available. If you can temporarily connect with Ethernet or a USB Wi‑Fi adapter and that works normally, it would strongly confirm that the built-in MT7921 is the issue.
It’s a combined modem/router located a few rooms away, and I’m not using a mesh pod. Another device works right beside it, so I wasn’t sure whether moving closer would really tell me anything.