I want to create async load of visual web part. Code behind (web part) needs some time to load data so I figure to create that in async way (on page load). Scriptmanager is placed in master page (ajax support is enabled) so I tried to do that with asp:update panel (+ update progress control - to be shown while data is not loaded) but i don't know how to do postback because I don't have any control which should be triggered to do postback (and I must not have any(!), at least to be visible). I found some documentation about SPG.AJAXSupport but solution for VS2010 doesn't have project for AJAXSupport, and solution for VS2008 (MOSS 2007) I can't open because it need some wild project templates which I can't find.