diff --git a/README.md b/README.md
index 95d024f..52ddb88 100644
--- a/README.md
+++ b/README.md
@@ -65,7 +65,10 @@ dkms autoinstall
 ```
 
 # USB 3.0 Support
-You can try use `modprobe 88x2bu rtw_switch_usb_mode=1` to force the adapter run under USB 3.0. But if your adapter/port/motherboard not support it, the driver will be in restart loop. Remove the parameter and reload the driver to restore. Alternatively, `modprobe 88x2bu rtw_switch_usb_mode=2` let`s it run as USB 2 device. 
+You can try use `modprobe 88x2bu rtw_switch_usb_mode=1` to force the adapter run under USB 3.0. But if your adapter/port/motherboard not support it, the driver will be in restart loop. Remove the parameter and reload the driver to restore. Alternatively, `modprobe 88x2bu rtw_switch_usb_mode=2` let\'s it run as USB 2 device. 
+
+Notice: If you had already loaded the moduel, use `modprobe -r 88x2bu` to unload it first.
+
 
 # Debug
 Set debug log use `echo 5 > /proc/net/rtl88x2bu/log_level` or `modprobe 88x2bu rtw_drv_log_level=5`