If you want to keep mining with your D3s for a long time, consider downgrading your frequency to the stock, 467. You will probably lose some money at 15GH/s but you will have a healthy miner that will last longer. If you push your miner to his limits you will end up with a broken miner and lose more money. JUST A RANDOM THOUGHT FROM A RANDOM GUY
UPDATE: There is another Pro when running the miner at a lower frequency besides running a cooler miner and a longer life span. YOU CONSUME LESS POWER = MORE PROFIT.
You can consult the following table with Frequency/HashRate mapping
Frequency => Hash rate
467 => 15 GH/s
487 => 17 GH/s
537 => 19.5 GH/s
Edit 1: Downgrading your D3 doesn't mean you lose money. In fact it can make you earn more.
If you mine with an overclocked D3 you get more HW errors which means less shares, which means that your hash rate in the pool is very much lower. Check your hash rate in your pool and not in your miner's interface. Your actual hash rate is the one your pool shows.
According to feedback, downgrading fixes most HW errors and the miner is more stable and consumes less power.
PS: You can try the app I developed to monitor all your miners at once. This will help you check the HW errors and temperatures and then you can decide if you want the downgrade or not.
https://github.com/anselal/antminer-monitor
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