What kind of temps do these run at?
My highest one reports 88C in one miner and in just one ASIC chain. Otherwise I've had around 60-66C avg temps all around. And I've heavily overclocked.
They are located in dry cold storage so ambient temperatures are low too (-6C atm), but this hasn't had any actual effect (-6C seems to be pretty much the same as +10C for them)...