Find "Network mode"
Press the menu icon.
Press Settings.
Press Wireless & networks.
Press Mobile networks.
Press Network settings.
Press Network mode.
Select network mode
Press 3G only, 2G only or 2G/3G auto.
3G enables you to achieve higher data speeds than when using GSM.
If you select 3G only, your phone can only connect to 3G networks.
If you select 2G only, you can't achieve high data speeds.
If you select 2G/3G auto, your phone automatically switches between the two network modes provided that you're within range of a 3G network.
If you select 3G only, your phone can only connect to 3G networks.
If you select 2G only, you can't achieve high data speeds.
If you select 2G/3G auto, your phone automatically switches between the two network modes provided that you're within range of a 3G network.
Exit
Press the Home key to return to standby mode.