What are the maximum number of Columns in ORDER BY clause in SQL Server?

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What are the maximum number of Columns in ORDER BY clause in SQL Server?
The maximum number of Columns in ORDER BY clause are Limited only by number of bytes.

Below link gives details regarding maximum bytes per ORDER BY Clause.
What are the maximum Bytes per ORDER BY in SQL Server?

Max Capacity For SQL Server 2012 SQL Server 2008 R2 SQL Server 2008 SQL Server 2005
maximum number of Columns in ORDER BY clause in SQL Server Limited only by number of bytes. Limited only by number of bytes. Limited only by number of bytes. Limited only by number of bytes.

http://msdn.microsoft.com/en-us/library/ms143432.aspx