>I have records in a table which have the exact same timestamp. This is because they are in the same millisecond. Is there a way to increase the precision in SQL Server to go higher than that?

As Naomi just said, there's DateTime2....also, you want to populate it using the function SYSDATETIME()

I believe DateTime2 goes down to the nanoseconds.

Here's a very good article that covers it:
http://blog.sqlauthority.com/2010/06/11/sql-server-difference-between-datetime-and-datetime2/