Recently I've been taking special notice of X-DNA matches, and I've come across several DNA matches where the X-DNA cM value is very high (but the atDNA cM value is very low).  I have first cousins with smaller X-DNA cM values, but their atDNA cM value always are within the expected amount for a first cousin.

An example from GEDmatch is:

[![enter image description here][1]][1]


I'm wondering if a match with such a large X-DNA cM value is always valid (or can this be a false-positive result)?  

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If this is a valid match, it posses a problem because the two donors/matches don't share a "common ancestor" (which should be at most a few generations away). 

  [1]: https://i.sstatic.net/qE5tf.png