Question: I have a ASP.Net WebForms page that has 2 drop-down lists (1 with 10 options, the other with about 600) and about 5 panels. Based on what value is selected from the drop-downs, other panels are made visible or invisible during async postback by querying a database.

My dilemma is this: The page is not fast enough on a slow connection, particularly during page load. When looking at the rendered page, the size of viewstate is large, even on initial load. Also, there is a large amount of data needing to populate the drop-downs, which could be contributing to the viewstate size.

Are there any suggestions to speed this page up?

Answer: 
Maybe load the options of the second dropdown list on-demand (e.g. using [AutoComplete of the AJAX control toolkit](http://www.asp.net/ajaxLibrary/AjaxControlToolkitSampleSite/AutoComplete/AutoComplete.aspx) or a similar control).
gzip html and json, reduce element count and anidation, simplify html, etceteras to reduce latency of traffic and rendering