Try using the attribute of the Page tag called
MaintainScrollPositionOnPostBack
set it to
True
.
The old and deprecated feature was called
SmartNavigation
and
MaintainScrollPositionOnPostBack
replaces it. With
SmartNavigation
there was less flicker with IE 5.5 and above.
If you need to make all the pages with the same attribute you can add it to the web.config file.
<system.web>
<pages maintainscrollpositiononpostback="true" />
</system.web>