Thanks man!
But still:
3. You bought an industrial miner, thats why its loud. If you put that fan on your miner wont run. Its 2100 rpm and 70cfm too weak. Dont change the fan.
http://www.overclock.net/products/delta-afc1212de-sp02-1120-x-120-x-38mm-extreme-hi-fan-dell-5pin-rpm-3900-rpm-air-flow-148-34-cfm-noise-level-51-dbaIts 150 CFM. Not 70. And native QFR is 210 CFM AFAIK. As native works at 4000-4500 actual speed it gives us 140-160 CFM. So AFC could handle that with lower noise? Im not smart ass - just wanna sort it out
4. No, not really. Why would you constantly be turning it off anyway? The whole point is to keep it as near 100% uptime as possible to maximize profits.
I mean several times or so while tuning. Not constantly of course)
You are replacing a 220cfm fan with a 150 cfm fan...and as I said the fan you want to use is 70 cfm too weak. 220-150=70 does it not?
Turning it on and off a couple times will not do any long term damage, maybe tell the guy that told you it was dangerous that its not the 1980s anymore lol