Post
Topic
Board Hardware
Re: ANN: BITMAIN has Tested Its 28nm Bitcoin Mining Chip BM1382
by
allcoinminer
on 02/07/2014, 17:15:38 UTC




As per the datasheet values below, S3 can be overclocked to 504Ghs and further to 554Ghs.
The stock clock speed is set in between 225M and 250M and voltage per chip lies in between 0.72Vand 0.75V per chip (366W/S3).
When overclocking to 504Ghs it will be consuming around 390W at 250M Clockspeed.
And when overclocking to 554Ghs the clock speed might be 275M and power consumption around  488Watts.
Further overclocking may not be possible, everything lies in finding the sweet spot frequency.
Take a look at DC-DC converters, they are a lot in nos, do you have any idea? Even this new chip consumes lower voltage than S1.

S3 Datasheet Values
Voltage(V) | Hash Rate(GH/s) | Current(A) | Total power(W) | W/GH
0.72                14.18                 10.40             7.49             0.528
0.75                15.75                 12.24             9.18             0.583
0.80                17.33                 15.20            12.16            0.702
0.85                17.33                 20.00            17.00            0.981



Questions on this chart.   do we come at the .75 volt setting stock or the .80 setting stock.

Seems to me that the real value is the .72 volt setting   at .528 w/gh  so my question is if we can do

 .72 volts and hash 14.18 GH/s   using only 7.49 watts a chip  can we do a little lower?

Would .69 volts  get 13.8 gh/s       9 amps   6.21  watts and  .450 w/gh?

 It would be really nice to find out the low end of these    along with the over clock

We need to try it and find out how much is practical.
Also when overclocking the temperature/HWE% need to be under lower.
The chip's operating temperature from specs is 35 but in 478Ghs/366W itself the temperature in bitmain's image its self is over 35.