Post
Topic
Board Mining support
Re: undervolt antminer s3
by
clizity
on 13/11/2014, 01:26:37 UTC
okay so just messing with adjusting the voltage of the ASIC chips my results are all over the place and I think I know why.at this point I'm assuming on the architecture of how the device functions but if I was building a cheap control system for voltage I would use some sort of processor to send out a control signal such as pulse width modulation or a 1 to 5 voltage as a referenceto some sort of voltage regulator. This appears to be the case if looking at the ASIC blades. There are several banks of voltage regulators leading down the card to several groups of chips looking at thisI have to assume that it's an open loop voltage control system. Meaning there is not feedback from each individual voltage regulator to allow the control system to know whether it's too high voltage or too low voltage and then adjust appropriately. Therefore I have to assume setting a voltage in the firmware is not precise control of the voltage to each individual ASIC chip. Also if you look at the design the board is laid out from left to right or right to left depending on how you look at it. This means the intake air comes in on one side of the board and then exits on the opposite side of the board therefore the temperatures across all these voltage regulators will vary greatly.  temperature differences will make voltage regulators drift in their output voltage. After observing this it would be my recommendation 2 leave the voltage at stock or to set it at the midway point. Setting it at the midway point would put the chips in the center at the midway point the chips at the inlet. At a lower voltage and the chips at the highest temperature location next to the exit at the highest point. By averaging all these together you would get a average efficiency across all the chips.

for the rest of my testing I set the voltage to. 7 volts. I was able to get a higher wattage efficiency out of the units by adjusting the clock more so than adjusting the voltage I attached a copy of some data I produced during these tests above.

by keeping units pretty well stock it appears that he can only fit about 7 units on a 3 kilowatt circuit.you can get the chip efficiency up by decreasing the clock but by decreasing the clock your overall hashrate decreases but efficiency increases. At the most efficient. With a clock of 100 he can place 18 minors on a 3000 watt circuit this would give him a higher overall hashrate than just using 7 miners at stock but would only lead to about 200 more Giga hashes. His return on investment would be ridiculous. Even adjusting the clock to 200 he could add 9 units to the circuit and would gain approximately a hundred and fifty more Giga hashes but with the price of ant miners he would be adding 600 to 700 more dollars to his setup which is just not a good return on investment.

I think the best way to optimize these units would be to set them up default and then increase the clock until you start seeing errors then decrease the clock so you don't get errors. Hardware errors in this scenario will lead 2 more wasted watts due to the fact units having to redo calculations.

I did observe that with higher temperatures the hash rate begins to decrease I was able to prove this by blocking the vents and watching my hash rate dropped by about a hundred Giga hashes. Therefore I have to assume that a more effective way of increasing efficiency would be to keep these units as cool as possible. Sometime in the future I will start experimenting with supercooling these units by using A heat exchanger inside of a 4 inch pipe feeding into the units. I will also try experimenting with other ways to cut wattage off of the units. I'm starting to think there are a lot of wasted wats inside of the circulation fans. Example would be that your power supply is not 100% efficient and DC motors are not the most efficient either therefore I have to assume y would you use clean power to run DC fans. I will attempt to remove the fans and replace them with AC units in an attempt to he could increase efficiency.so far I've been able to get objects up to a hundred degrees by just using the exhaust air on these units. Which leads me to think we may be able to reclaim wattage with the use of a device such as a thermal electric generator.

I will continue to try to work on my units to make them the most efficient as possible in my spare time its in my best interest to do so because I plan on being independently rich using Bitcoin miners.until then donations are greatly appreciated to help further my research which I will continue to share with everyone on the post form. When I get something new I will post it in this post forum as well as maybe make a new post.

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