I have a joomla site and it works fine with all the modules. I installed my site in another server but it delays too much due to Twitter module and weather module wich of course read rss feeds. If i disable these modules the site's performance is fine. Can oneone tell me what can be wrong in the new server. Thank you in advance.
Typically on Joomla! modules for Twitter/Facebook/Weather do very little on the server - the bulk of them use Javascript to retrieve the data from the source website (i.e. not your website).
Given that, any slow-down is usually related to:
Use your browsers profiling tools (Chrome, Safari, Firefox) to determine exactly what's going on - you'll probably find it isn't your server.