If you give me some of that hashrate I'll throw you a couple of hints!  :-)

But because I'm a nice guy here's a couple quick ones for free:
  Increase your clock to 1600 ~ 1750, it's the only way to mess around with voltages on Linux
  Don't use Cuda 1.15 on linux, for whatever reason it performs much worse than 1.14 -- but in windows 1.15 works much better apparently.
  Lower your intensity a bit, try 3800


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there is no place for a lot of heat in the room, 3 x6 rtx 3090 rigs and another x7 rtx 3070 non lhr, thanks for the advice, I will try intensity 3800