Filters not working as expected

Hi guys, I am trying to create a simple dymanic filer based on computer name.  I used the query builder and it is pulling in more results than I want.

Want to filter by name starting with DEN.

Have my query setup as Computer including Windows Workstations

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Added a Parameter with value DEN%

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And set the filter to use it.

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Am getting computers that's name do not start with DEN and ones that start with DEN.  HELP.  :)

Thanks

Ash