DateTime mismatch when they are the same (Possible SQL Server issue)

I am using Dapper to pull information from PostgreSQL and insert/update it in SQL Server.

I am using FluentComparator to check to see if the existing record is the same as the newly retrieved one. I have read that the datetime value saved in SQL Server may be a little different from the value in the update/insert statement. I am finding as a result, the match fails. Is there a way to set the precision range for datetime items?