The 8812B draws significant power. You must use a powered USB hub, or the Pi will crash due to undervoltage.
sudo usb-devices | grep -A 10 Realtek
| Feature | RTL8188F | RTL8811C | RTL8812B | | :--- | :--- | :--- | :--- | | | 2.4 GHz only | Dual (2.4 & 5 GHz) | Dual (2.4 & 5 GHz) | | Max Speed | 150 Mbps | 433 Mbps | 867 Mbps | | MIMO | No (1x1) | No (1x1) | Yes (2x2) | | USB Required | 2.0 | 2.0 | 3.0 (for full speed) | | Monitor Mode | Yes (with patched drivers) | Yes | Yes | | Best For | Printers, IoT | Everyday browsing, streaming | Gaming, VR, large transfers | | Average Price | $5 | $10 | $18 | | Obsolete? | Yes (Wi-Fi 4) | No (Wi-Fi 5 entry) | No (Wi-Fi 5 mid-range) | rtl8188f-8811c-8812b
sudo sed -i 's/wifi.powersave = 3/wifi.powersave = 2/' /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf sudo systemctl restart NetworkManager The 8812B draws significant power