Case Senitive SQL Quary Using Datarow

I have in SQL Table1 the following values in
Field1:

ABC
ABc
AbC
abc
aBc
abC
  Select Field1 From Table1 Where Field1 = "AbC"

I get all six records, not just the one record (AbC) that I want to retrieve. How do I tell the select statement to be case sensitive?

 
my asp.net statement is given below
 
 DataRow dr1 = ds.Tables["Login"].Select("UserId ='" + txtUserId.Text + "'And Passwords ='" + txtPassword.Text + "'")[0]; 
i m using datarow
so i need a help
i have quary but i don;t know how can use
  DataRow dr1 = ds.Tables["Login"].Select("UserId ='" + txtUserId.Text + "'And Passwords ='" + txtPassword.Text + "'where CONVERT(binary(5),Userid)=CONVERT(binary(5),'" + txtUserId.Text + "')'" )[0];                                     
this give me error "Where condiction need operator"
waiting for reply