This page contains links to resources that are useful when installing SQL Server Express, such as installation guidance and information on how to troubleshoot common installation problems.
SQL Server Express 2005
SQL Server Express 2008
SQL Server Express 2008 R2
For processing purposes, SQL Server Express recognizes the additional processors that are available on a computer that has a multiple-core CPU or an HT Technology-enabled CPU.
For example, if you have a dual-core CPU, SQL Server Express starts two separate schedulers. Both schedulers are available for SQL Server Express to use. This behavior lets SQL Server Express do some parallel processing within the limits of the one CPU that the product is using.
For more information, see http://support.microsoft.com/kb/914278.