Methods and apparatus may be used for selecting power saving mechanisms in a wireless transmit/receive unit (WTRU). For example, a WTRU may support at least power saving mode (PSM) and/or extended discontinuous reception (eDRX) mode. The WTRU may send a request message including parameters associated with the supported power saving mechanisms, such as an active time for PSM and a preferred DRX value for eDRX mode. The WTRU may receive an accept message including at least one selected parameter indicating the power saving mechanism for the WTRU selected by the network (NW). The WTRU may activate the selected power saving mechanism, and may start a validity timer to define the duration of use of the selected power saving mechanism. In another example, a WTRU configured to use eDRX may receive paging signals for system information (SI) change over a prolonged Broadcast Control Channel (BCCH) modification period.