Hi Clive, They are all different data modes. UMTS is not supported in the UK. Dual mode is always best, because if you wander out of your home network, it allows your phone to search for a stronger signal. All the best Steve -----Original Message----- From: talks-uk-bounce@xxxxxxxxxxxxx [mailto:talks-uk-bounce@xxxxxxxxxxxxx] On Behalf Of Clive Pallett Sent: Tuesday 7 October 2008 10:03 To: Talks-UK Subject: [talks-uk] Network modes and battery life Hello fellow listers, Does selecting a network mode affect the battery life on a mobile phone? My Nokia N91 has three network modes, dual mode , UMTS and GSM. I am on T-Mobile and I can use the dual mode and GSM, but when I select UMTS the phone goes off-line and I lose the network connection. When I select dual mode and check the network status, I sometimes hear 3G, so the phone must use this connection when available. Can someone on the list please explain what these modes mean and how they affect battery life. As I use Talks this shortens the time between charges, and I know you can adjust the backlight and display settings. Any help most appreciated. Thanks in advance. Best wishes, Clive pallett