When it comes to resolving table fragmentation, the basic checkout you perform is to run DBCC INDEXDEFRAG or even run DBCC DBREINDEX statements. As per the default configuraiton SQL Database Engine allocates a new extent to an allocation unit only when it cannot quickly find a page in an existing extent with sufficient space to hold the row being ...

Source: Knowledge Base Product: Microsoft SQL Server 2005 Standard Edition & SQL Server 2005 Enterprise Edition Notification Contents: New and All Modifications FIX: The performance of insert operations against a table that contains an identity column may be slow in SQL Server 2005 http://support.microsoft.com/kb/940545/en-US...(read more)