I think your problem is the Avexir ram, others have reported similar problems with the same ram as yours and have solved this problem changing ram modules as you can see here Re: NUC6i3SYH Random freezes
Sorry to have to tell you that probably you have to change your ram.
Thank you topix for the reference to the other thread related.
Please do check that your RAM is compatible with the unit you have to get the proper performance.
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Thank you for providing us with your outcome on this and I am glad to hear that you were able to get this to work properly.
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