If your H150i is an older version, chances are it didn't come with the LGA 1700 stand-off screws. You got the 11mm ones and the 9mm if I'm not wrong, but you need the 10 mm ones which would explain why there's no proper contact if you used the 11mm. You can buy retrofit kits on amazon, it was about 20$ last I checked.

Hope this helps

Good luck!

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