You install an instance of Microsoft SQL Server 2005 on a computer that has many processors. You upgrade to SQL Server 2005 Service Pack 3 (SP3) or to Microsoft SQL Server 2008. You run a query that uses the Like operator in the WHERE clause or that uses a string comparison function, such as the CharIndex() function. When you run the query many times on multiple connections at the same time, the CPU usage reaches 100 percent, and the server performance decreases significantly.
Then refer the Microsoft article and apply the cumulative update