Topic: Ultra Under-overclock image for A2 Innosilicon by Emdje - V5.0 - page 7. (Read 79798 times)

I had went with single parallel option on the 10k, seemed to work fine, running at 0.94v although math says 0.92v, wish I had done some more testing before hand though but hey that is the way it is. Good job!, while crude this is a chart I did with this board, I just ran 50k shares at each frequency, I should have ran more but in the interest of not taking 3 hrs for a test.

Frequency| 1100 1120 1140 1160 1180 1200 1220 1240 1260 1280 1300 1320 1340 1360 1380 1400

HW errors| 2 2 0 4 0 5 4 1 10 9 17 14 36 43 90 89

Current on 12v| 14.28 14.45 14.67 15.06 15.23 15.46 15.64 15.76 16.13 16.37 16.63 16.75 17.2 17.44 17.53 17.89

Watts 173.502 175.5675 178.2405 182.979 184.8922 187.6844 189.8696 191.3264 195.8182 198.5681 201.7219 203.1775 208.636 211.1984 212.2883 216.6479

So I decided to take a crack at overvolting and overclocking my A2 110. The guide provided earlier in this thread does not cover the V4 boards, and I could not find one on the forums so I decided to post it here.

The A2 110 V4 blade buck controllers are based on Linear Technology's LTC3856. Datasheet. Following Pg 29, the feedback resistors will be connected to FB (pin 2), and dictate the output voltage via the equation Vout=0.6*(1+R_B/R_A). The controllers are set up to use the chip's diffout configuration, but the equation remains the same.

There are 3 different controller layouts on this board:
One side
Other side
End of blade

As we see in the photo, there are two resistors labeled 01C and 66B, 10kΩ and 4.75kΩ respectively.
This yields a stock voltage of 0.6*(1+4.75/10)=0.885V

I figure I want around 0.925V, following the target voltage earlier in this thread.

There are two ways to handle this. We can decrease R_A or increase R_B. I had a lot of 24kΩ and 27kΩ resistors left over from a previous project. It just so happened that if I used one of each value in parallel with each R_A and R_B, 27kΩ||10kΩ=7.297kΩ and 24kΩ||4.75kΩ=3.965kΩ yields 0.926V.

So I soldered a 27kΩ across the resistor marked 01C and a 24kΩ across the resistor marked 66B. I ended up with ~0.933V on average.

If you want to only solder one resistor, R_p in parallel with R_A (01C), it would follow this equation: Vout=0.6*(1+(4750/(10000*R_p/(10000+R_p)))). Solve for R_p given a target Vout.

I've yet to do long term overclock testing. I'm testing 1200MHz stability for now. On average the power consumption is up ~2A to ~15A on the 12V rail. My stock power supply is not able to supply more than 4 blades stock, much less 4 overclocked blades. I just split the load half and half between the stock power supply and another 1kW power supply. I should have some numbers soon.

After 1hr of 1300MHz, it seems successful. I'll run it overnight and see how it fares.

Also check the polarity of the power going to the boards with the original power supply. I had to switch the plus and minus with the pcu I am using due to the connector being different.

So nothing comes on? I don't really have a A2 miner but I have see photos of the controller board, I am going to assume that you do have power on the 12 and 5V rails , I don't know if the 3.3v is needed nothing that I have seen needs 3.3 just 12 and 5 and it looked like there might have been regulators on the board already for a 12->5 conversion. I would check power on the Rpi, you should be able to probe the capacitor at the normal input jack , if you got 5v there and it is still not on then you might have a big problem. On the connectors going down to the hash boards I *think* that pins 2&4 are +5 and 6,8&10 are gnd so you could check that as well. Really I think all the controller board does is bridge on the ATX psu and power the PI, I dont really know why it would need +12 at all unless it does some basic power monitoring to see if there is power there.

This are all guesses really , if you could get me a good straight on shot of front and back, I am working on a new controller board, I just only have one card I have adapted to the RPi, that power supply is pretty $$$ I hope you didn't have to pay that much for it.

The PSU is a PFE1100. It's breakout board outputs 12v and 5v, and I'm using a buck converter to make 3.3v from the 12v output.

What server PSU are you attempting to use? How much of it does not work, any , some lights or just dead? have you checked to see if there is output on the lines?

Seems like betarigs is out of game for good, so Im back to 4.0 and MRR.

I have a question that hopefully someone will be able to answer.

I'm trying to run my 60 and 88mh units using a server power supply. I cut the ATX harness off of a dead PSU, and connected all of the 12v 5v and 3.3v wires on the harness to the appropriate server PSU outputs. I thought for sure that would be all that's needed, but the controller doesn't work. Any idea what I'm missing?

I am not sure will have to check that.

Hi all, Emdje, did you manage to fix pool-switching problem (mainly betarigs) on 4.0 image? E.g. by putting back the old stratum, but still supporting the xnonce? Thanks.

The stock fans run full power, they cannot be adjusted. I have put different fans in it, that are more quite and can be adjusted (by thermocouple, although I use them at 100% speed) in speed. (replaced the one stock fan with 3 of these, less power, less noise)

How do you modify the fan power output?  Are PWM fans compatible with the miner?  I'm looking for a way to stop the fans from spinning at 100% all the time, my room temperature is cool enough where it doesnt need to run at full speed 24/7. .. besides that, they're ridiculously loud.

thanks

Well in typical fashion when you want something it gets lost in shipping

Looking at the two boards I have it looks like there are two chains of hashing chips, the one board that has the 10 chips on it has 10 LEDs for the chips, the other board that has 12 slots but 10 chips only has 8 LEDs for the chips 1-4. Does anyone know how many different variants of these boards there are? Also can just the boards be bought and anyone have a price. The 10 chip one is  green and says it is official the other is blue and just has a version number.

I hope to have some high resolution photos next week and if I am lucky some X-Ray images at some point.

That would be great info to have. thnx 

Hi everyone, I am a little late getting into the game but I have picked up what is described as an 110Mh A2 terminator with two bad blades shipped with two replacements. I got the two replacement blades today and looking at them one is a 10 chip board as I would expect and the other is a 12 with two missing, I notice a small loop back resistor. He said they were working replacements sent from innosilicon, they are defiantly pulls and are rough looking esp around the power connectors. I plan on taking a lot of photos, I haven't been able to find much in the way of schematics and such but plan on making a few.

Anyway hope to help with anything I can,

Jarrid

If I understand it correctly and it is not a typo and you mean reseating intead of resetting than that probably means checking all connections. Plugging everything off and on again.

Very interesting., This is pretty cool.

Sorry for the late reply, it seems I don't get an email anymore when there is a message in the topic.

There is no config file, but you can add it to the index.php on line 20

Hope it helps.

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