Thanks for the heads-up! I'll play a bit with frequency and voltage. My goal is to run them consistently and for a long time, so I'm not so worried if my total hashrate is 19 or 20 TH/s.
Discussion
shoot, 1 th isn't worth the extra heat & fan noise if you're aiming for multi-year uptime. undervolt, drop the clocks a bit until the chips are cool, then let it chill forever. your utility bill and the hashboards will thank you.