Grant Fritchey has a nice article on the Simple Talk site that discusses the basics of measuring and tuning performance with SQL Server 2005. It’s a good read.

I am always amazed at how many questions I see in the MSDN SQL Server Database Engine forums that are along the lines of:

"My database server is not performing well. What could be the problem?"

When you have a performance issue, you need to start collecting data to narrow down the problem. Grant’s article is a good starting point.