The same config with 16 cards + without oc work well. so i don't think that there is trouble with intesivity.
What does "die very fast" mean? How far it gets and how it dies is very important.
Is there an error message? Does it start hashing?
And how many is "16 cards +"? What is the maximum that work?
i have tested 16 18 and 19 cards. 17 haven't tested. 16 works just fine and i have stoped experiments.
when it is 19 gpus it started hashing always after intensity sets and sometimes it even 45 seconds shows hashes of 4 or 5 cards.
when it was 18 gpus it die faster than 19gpu config in stage of intensity sets.
I can't now show error's because i have removed 3 cards. just ccminer crashed system was stable.