$bandeau_post = get_transient('top1_bandeau_post');

	
if (!is_array($bandeau_post) || count($bandeau_post)==0) {
		
	$args = array(
		'posts_per_page' => 5
		);
	$bandeau_post = array();
	$bandeau_post = query_posts($args);
		
	set_transient('top1_bandeau_post',$bandeau_post,60*60*$timeout);
}
	
foreach($bandeau_post as $post) :
        setup_postdata($post);

// the display code

endforeach;

http://www.mp2013.fr

Snippet to show a simple use of the transient API when querying posts.

Query posts and cache the query

wordpress, query, cache

PHP