First of all, you can't add a milisecond to a datetime, you need to use datetime2.

Here's an example, if you remove the CAST, you'll see what I mean.

SELECT TOP (500) DATEADD( ms, ROW_NUMBER() OVER (ORDER BY s1.[object_id]), CAST('2013-07-30 08:20:40:010' AS datetime2))

FROM sys.all_objects AS s1

CROSS JOIN sys.all_objects AS s2