Topic: ANTMINER C1 Discussion and Support Thread - page 16. (Read 129136 times)

The numbers you seem to have faith in claim that at 67% of normal wattage he's getting only a 79% decrease in hashrate.  That's even if his wattage is correct at normal frequency and voltage.

At normal frequency and voltage he claims 790watts.  At normal frequency and voltage after an hour I had 1008GH/s but at 818 watts and after 2 hours I had 1002.88 @ 819watts.  

I see from numbers on the S5 forum that my cheap power supplies run about 8% less efficient.  If I reduce my power usage by 8% I get 753 watts.  So, maybe my supply isn't 8% inefficient.

At 250M/0760 I got 1233GH/s/w or .811w/GH/s.
At 250M/0675 I got 1228GH/s/w or .814w/GH/s
At 243.75M/0675 I got 1242GH/s/w or .8059w/GH/s

So, you can see why I find it incredible that somebody went from .783 down to .66 because we're talking about miner efficiency change not supply efficiency change as supply efficiency shouldn't change that much in that wattage span.

As I said previously, I did see better figures at 200M on an S3 at stock voltage but it was during the coolest part of the day and ambient temperature seems to be a critical factor when measuring efficiency.  

I have not tried 200M/0675 yet but I will eventually.  

Oh, and my pumps and radiator fans are on a supply divorced from the C1 and not included in the calculations.

Thanks for warning about MHs.  I did make a mistake on not using GHs.   

And your correct about same chips.  I would guess we will be close to S3 numbers, but cannot say for sure this is one miner I have not underclocked yet.

I ws looking at the .66 which would be watts per gigahash not megahash?  The efficiency would seem very good unless you're off by the difference between megahash and gigahash which then would be quite bad.  I looked on the S3+ for the frequency and voltage which might correspond as S3's have the same chips as the C1.

But I couldn't find your reference.

Looking at the GHs i think it is C1.   No S3+ can do 800 GHs.   And it's to high for S5.  

So i'm sticking with guess of C1

Could you locate that post please?  Your's seems to be the first reference to 0.66W/Mhs on this or the S3+ forums when I search 0.66W/Mhs.

I tried 0675V/200 - working but with  x
With 0700V I never had any x on the same machine.

Just did this yesterday, kill-a-watt, 118vac, ambient 79.95°F, 29.52inHg, 250M/0760, 1002.88GH/s(avg) 819watts, 1.233GH/s/w .811w/GH/s.

Then at ambient 77.9°F, 29.54inHg, 243.75M/0675, 982.76GH/s(avg) 792watts, 1.241GH/s/w .8059 w/GH/s.

I'd decided to run my C1's at 243.75M/0675 to reduce the current away from max on that circuit.  After I characterize my S3+'s I'll come back and look at 200M/0675 because that frequency agrees with best I found on an S3 but happened to be at the coolest point in the day.


I'd appreciate your feedback when you get to 80°F ambient.  I know these are less efficient power supplies and my initial application was at ½ full load capacity but with the C1's they at 56.9% of full capacity each.

Running at 243.75M/0675 @ 79.9°F my hashboards read 35,38,36,38 & 981.12GH/s(avg).




~700 feet above sea level

soy

I had wondered once about an air mass flow sensor and if it would applicable here.  But, the LM75A could generate data that would simulate an air mass flow sensor output.  So, air flow ability to cool ASICs should determine fan speed.  If fan speed is increased according to a formula calculated at sea level it would be less than optimal on a humid day or at higher altitudes.  If the fan speed is determined by the LM75A state and increased to lower the LM75A output, then the air's mass is less a factor.  I wonder which it is.

120vac recorded at the wall with a kill-a-watt. It's 21-22C around the miner 32C in the miner web admin. It was 36C with the default setting.

Wish he had included F° & inHg.  And is the supply on 120vac or 230vac?  I'm jealous 'cause I don't get anywhere near that W/GH/s with my exceptionally cheap power supplies @ 250M/0760.

I won't take away and turn this into a basing thread.  Just syscooling and batch one was not a good mix.  I have had lots of bitmain products and never been treated like I was during that.  But again it's in the past and I think Bitmain did a great service to buyers to carry the product themself.  It was cheaper and you get better service.

And also thanks for sharing underclock I appreciate that. 

Yes by chance I buyed in the second batch.

Thank you for posting these.  I appreciate you sharing them.  As it's getting summer time I chances are will be looking to underclock soon.

I'm not going to fight you over it, your comment is not needed.  I will ask did you have the first rendition of electrical wire and get first batch as soon as they started shipping?  I was thinking you were later on in this thread buying a decent amount after they first started shipping.  I think your experience is different then many who got very first ones.

Now that people are getting them through bitmain kits it's cheaper price and better customer service in my personal opinion.

I tested underclocking-volting the C1.

The best setting was suggested by another user 2 weeks ago:

675/200 530W  803Mhs 0.66W/Mhs
760/250 790W 1008Mhs 0.783W/Mhs

FYI I have an EVGA 1300W gold.

No one was forced to buy the kit from syscooling. There is a lot of place where you can buy watercooling supplies.

I find it interesting Syscooling was last Active: March 21, 2015, 09:35:43 AM

I am just hoping this means there will never be a product again with them as a supplier of parts.   I would love a C2 with a proper water cooling vendor if they ever do it.

I think you will love the tank.  I have been running it so long on those and no issues.   I have a extra bottle of coolant in case of summe heat needing it.

So far it's been able to handle mid 70 degree days and no issues.

Summer coming.  Adding a little water to the tank every day or two.  Without the sharp cornered Syscooling and only the champer edge Syscooling in place no refilling necessary.  So, tho there is no detectable leak a little water is going somewhere with the after market Syscooling pump in place.  With summer in mind I bit the bullet and bought one of those large tall tank pumps but from China.  No rush I figure.

I personally went with coolant and it might be luck but I have never got the "disease" (Also using different pumps could be part of it).   Only bad thing about coolant is if you syscooling pump leaks then you are loosing money from re-buying coolant.

I used a water-cooled Antminer  S5  only 48 hour with distilled water .  After the first over heating due to the pump failure and  switched off, I also got this "disease" . See the photos from opentoe
https://bitcointalksearch.org/topic/m.10386451

Treatments with anti-freeze and everything is fine.