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July 29th, 2025 14:20
Extremely Slow Wi-Fi on Dell Laptop with Intel AX211 - I'm Out of Ideas
Hey everyone,
I'm hoping to get some help with a persistent Wi-Fi issue. My Dell laptop has been suffering from extremely slow and unstable Wi-Fi for a while, even though both the laptop and my router are modern and capable of high speeds.
The Problem:
I have a 500 Mbps internet connection, but my laptop only gets around 80-100 Mbps. All my other devices on the same network (phone, tablet, etc.) easily reach the full speed. So, the problem is definitely isolated to this one laptop. For Example: My S22 gets on the exact same location, in the exact same network (5Ghz too) with the exact same speedtest-server, up to 450 Mbps, my Laptop only 23!
System Specs:
- LapDell inspiron 16 plus 7640
- OS: Windows 11
- Wi-Fi Card: Intel Wi-Fi 6E AX211 (the original, factory-installed card)
- Router: Telekom Speedport Smart 4 (I'm in Germany)
My Diagnosis
After a lot of digging, I'm fairly certain I've found the root cause: the laptop is stuck in 20 MHz channel width mode.
When I check the Wi-Fi status in Windows, the link speed to the router is only about 144-287 Mbps, which is typical for a 20 MHz connection.
The smoking gun: In Device Manager, under the advanced properties for the AX211 card, the dropdown menu for "Channel Width for 5GHz/6GHz" is completely missing the "Auto" or "80/160MHz" options. The only available choice is "20 MHz".
My theory is that the Wi-Fi card isn't receiving its regulatory domain (country code) from the system, forcing it into a global "safe mode" with minimal performance and channel width.
Here's a list of everything I've tried so far without success:
- Router checks: Rebooted and checked all router settings. The 5GHz band is active, and as mentioned, other devices work perfectly.
- Every driver imaginable: I've tried drivers from Dell's support site, directly from Intel, via Windows Update, and even the Intel Killer Performance Suite.
- Clean driver reinstall: Completely uninstalled the device (checking the "delete driver software" box) and reinstalled from scratch.
- Windows-level repairs: Performed a Network Reset, ran sfc /scannow and DISM, and set power options to max performance.
- Checked for interfering software: Mobile Hotspot is disabled, no third-party VPNs or antivirus suites are active.
I'm truly at a loss. The hardware seems to be fine, but something within Windows is preventing it from working correctly. Does anyone have any ideas what else I can try before I resort to the "nuclear option" of a full Windows reinstall? Could there be a hidden registry key or a Windows policy causing this?
Thanks for your time and any help you can offer!!!!!!!!