Issues with Marvell AVASTAR wireless-AC Network Controller on Surface Book 2

Rose 0 Reputation points
2026-10-19T19:38:02.78+00:00

I'm having really disruptive issues with my Wifi since switching my internet provider to Tmobile 5g home internet. Sometimes when I turn on my surface book I have extremely low internet speeds, of 0.8mbps up to 1.2mbps. I usually end up fixing this by disabling and enabling the Marvell network adapter in my device manager, but sometimes I need to spend 40 minutes doing this until it starts working again. Once it works I get back to high speeds of 100-300 and as long as I don't restart my computer it usually stays working all day.

Things I've tried

  • turning off "Allow the computer to turn off this device to save power"
  • putting it on 5ghz only
  • uninstalling device and reinstalling
  • installing older driver or rolling back

I am on the most recent Win 11 update

Surface | Surface Book | Network
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  1. AI answer

    2026-10-19T19:39:08.9266667+00:00

    Capture the Wi‑Fi state while the connection is slow—before disabling the adapter—then compare the Surface on another network to determine whether the failing side is the Marvell link or the T‑Mobile gateway.

    1. Capture the failure before resetting anything

    Disabling the adapter changes its state and can remove useful evidence. When the next slow startup occurs, open Command Prompt as administrator and run:

    netsh wlan show drivers
netsh wlan show interfaces
netsh wlan show networks mode=bssid
netsh wlan show wlanreport
ipconfig

    show interfaces records the connected band, channel, signal, receive/transmit rates, and adapter state. show wlanreport creates an HTML report containing recent wireless sessions, disconnect reasons, and adapter information; the command prints the report’s location. Also note the exact time the slowdown occurred. ^1^

    In the ipconfig output, find Default Gateway, then test the local Wi‑Fi path:

    ping <DefaultGateway> -n 30

    Interpret the result:

    • High latency or packet loss to the gateway: the problem is between the Surface’s Marvell adapter and the T‑Mobile gateway.
    • Gateway ping is stable but internet performance is slow: investigate the gateway’s cellular/WAN connection, DNS, or T‑Mobile service rather than repeatedly resetting the adapter.

    2. Isolate gateway compatibility

    While the Surface is in its slow state:

    1. Test another device on the same T‑Mobile Wi‑Fi.
    2. Connect the Surface to a phone hotspot or another router and repeat the speed and gateway-ping tests.
    3. Compare the results without first disabling the Marvell adapter.

    Microsoft’s troubleshooting flow treats a network that works on another device as evidence pointing toward the Surface; if multiple devices are slow, the router or service is the likely side to investigate. ^2^

    Because 5-GHz-only mode has already been tested, there is no reason to repeat that setting. If the Surface is slow only on the T-Mobile gateway, review the gateway’s available compatibility, channel, security, and band-steering settings with T-Mobile using the WLAN report’s channel and radio-type information.

    3. Check Surface firmware separately from Windows Update

    Being current on Windows 11 does not necessarily confirm that every previously released Surface driver and firmware package is installed.

    1. Open the Surface app.
    2. Expand Help & support and check the update status.
    3. Select Check for updates.
    4. In Windows Update, install applicable optional Surface driver updates, then restart.

    The manual Surface driver and firmware package is also available through Microsoft’s Surface download page. ^3^

    Surface Book 2 driver and firmware servicing ended on June 30, 2023, so it will not receive newly developed firmware or Marvell fixes; previously released packages remain available. ^4^ ^5^

    4. Conditional fallbacks

    Since power management, driver reinstall/rollback, and 5-GHz-only mode have already been exhausted, do not repeat them.

    • If Surface updates are complete but the issue occurs on every Wi‑Fi network: run Start → Surface Diagnostic Toolkit and complete its tests. If unavailable, use the Surface app’s Get help function. ^6^
    • If the WLAN report shows normal association but IP or DNS failures: reset the network stack from an elevated Command Prompt: 
        netsh winsock reset
  netsh int ip reset
  ipconfig /release
  ipconfig /renew
  ipconfig /flushdns
      Restart afterward. These commands reset Winsock/TCP-IP state and renew addressing. ^7^
    • If that fails: use Settings → Network & internet → Advanced network settings → Network reset → Reset now. This removes and reinstalls network adapters and resets their settings, so VPN clients or virtual switches may require reconfiguration afterward.
    • If failures occur across networks after diagnostics and reset: test with a USB Wi‑Fi adapter. Stable operation through USB while Marvell remains slow strongly isolates the built-in adapter path; use the USB adapter as a workaround or submit the Surface for service.

    References

    1. Advanced troubleshooting wireless network connectivity
    2. Troubleshooting Wi-Fi connection on your Surface | Microsoft Support
    3. Download the drivers and firmware for Surface | Microsoft Support
    4. Surface devices driver and firmware lifecycle for Windows-based devices
    5. Surface Book 2 update history | Microsoft Support
    6. Diagnose and repair problems on your Surface | Microsoft Support
    7. Fix Wi-Fi connection issues in Windows | Microsoft Support
    AI-generated content may be incorrect. Read our transparency notes for more information.

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  2. S.Sengupta 33,091 Reputation points MVP Volunteer Moderator
    2026-10-20T06:37:03.3466667+00:00

    Most likely the Marvell adapter is coming up in a bad state at boot. Try these in order:

    Turn off Fast Startup: Control Panel > Power Options > Choose what the power buttons do > untick “Turn on fast startup.”

    Set Wireless Adapter Settings to Maximum Performance: Power Options > Change plan settings > Advanced settings.

    Split the T-Mobile gateway’s 2.4/5 GHz names in the T-Mobile app, connect only to 5 GHz, and try 20/40 MHz channel width.

    Quick fix instead of 40 minutes of toggling: run Restart-NetAdapter -Name "Wi-Fi" in admin PowerShell.

    If none of that works, a cheap USB Wi-Fi dongle is the reliable permanent fix.

    When it’s slow, check whether your phone is also slow on the same Wi-Fi. If it is, the problem is the gateway, not the Surface.

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