Yes, 650 fixed frequency firmware

After several says trying different firmwares I can confirm the following;

With original bitmain LPM firmware + original bmminer, just changing the frequency inside advance panel and modifying through css the fan speed control to 100%, right now I have my two antminers s9, one 13.0TH s9 running to 675 = 14.237TH and 73C and the other s9 14.00TH running 750 = 15.931TH and 80C and almost no hw errors and 1600w psu. So I´m not experiencing anymore the heat problems.

Well, I have tried with all of them and changing frequencies but nothing improve, always same problem with high temps. Answering to your question, yes, I tried flashing 650 fixed frequency firm first and from there just swapping bmminer file for your file. For example, I have tried with bmminer 880 and frecuency 650 onwards, like 656, 662, etc till 762. With all of them I get same problem. Thanks for your help !

Hi Taser, one question please;

I have two antminers s9, ( 13.5 and 14.0 ) and 1600w bitmain psu. The temps I´m getting with stock firmware are of 75C.

I have tried with every single bminer you have attached and different frequency options but the temps increase to 110C and the antminer turn off itself after a few minutes running. What I´m doing wrong ? Because I can see here many successful antminer users getting more hashing and keeping low temps, is because they are using any kind of refrigeration ?

Thanks for your help !