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Hope, I am in the right place to ask a noob question. I was comparing Antminer with Spondoolies and have a question regarding the OC. In case of Antminer the frequency can be seen on the miner dashboard, what happens in case of Spondoolies. All I have found is Voltage/Watt range (Max and permissible) no mention of any frequency. Can somebody guide me to a better understanding?

under 'asic stats' on the spondoolies you can see the current frequency for each individual chip, based on temperature and other optimizations

eg:

https://i.imgur.com/gsAC0LH.png

My simplistic understanding of the SP20 is that the internals of the machine will try and adjust the frequency upwards, until it works at the "Max Voltage" you can set. In other words you don't set the frequency directly, but rather dial the the voltage up and down (or the power), and let the hardware manage the frequency within the limits you have set.

There is a "Basic Settings" button on the "Settings" page that can get you started. You can then dial the voltage up/down, or the power (down from 288) to try and get what you are looking for. When you make a change, you'll need to let it settle in for at least an hour to make sure that it's really hit it's stride, and the parts have gotten fully warmed up.

The general consensus is that despite the advertised 1700 GH/s rate, a more realistic top end is probably closer to 1500 GH/s. For maximum speed, you'll also need a cool environment to make sure the ASIC's don't "thermally throttled". You'll also need a solid power supply with quality PCIe cables for top speed.

Reaching for top speed will also result in poorer efficiency (i.e. more Watts/gh). There are a couple of SP20 threads with lot's of good experience and suggestions.

Best thread is philipma1957's : https://bitcointalk.org/index.php?topic=872014.0

And I would agree I would not go twords the 1.7 mark you will have to do a pretty high OC.  I think where the SP20 shines is it's underclock.  Personally I am running a underclock on my SP20's to get that more efficient usage of electricity.  In my case I make more this way.

I'll 2nd the notion of the SP20 "underclock" (i.e. reduced voltage/power) and it's flexibility. It will hang right in there with an S5 in terms of efficiency at 1.15 GH/s. Personally I am setting for "power usage" and right at about 1170 GH/s and 600 watts. As the weather warms up, I'll dial that down for lower power, lower speed, lower fan/noise, and lower heat. I am hoping to be able ride it through the summer and maybe speed back up in the fall here in Minnesota. We'll see if difficulty and Bitcoin price will dash my hopes or not.

Severe underclocks of

.585
.585
.585
.585


max

.589


watts

180
180
180
180


reboot
700

 are possible on some not all machines.

the settings above  will get you close to 850-925  gh  and use about  380 watts.

these are about as low as you can go.  don't try them unless you have a pre programmed micro sd card or at least 2 sp20's

If you go this low and the machine does not start  it can be difficult to recover and the micro sd card maybe needed. With a higher set of clocks.

this is a decent setting  for around 1300 most every sp20 will be able to start at these numbers
http://imagizer.imageshack.us/v2/1024x768q90/910/2wUncw.png


http://imagizer.imageshack.us/v2/1024x768q90/540/jHTi9p.png



Notice 1 warm chip    here is why   Fan>>>> chip  chip >>>> air exits       so the first chips warm air hits the second chip.

I never let a chip run over 115c  ..  I had 16 of these machine with a zero failure rate  I mostly ran them at 1300.



http://imagizer.imageshack.us/v2/1024x768q90/673/htlkaO.png

On one hand the self management of clocks is great on the other, its sad for those who want to tweak each chip freq individually. I think they could run much more efficiently if we could hand tune clocks / voltages. When these autotune they tend to drop clocks down way to far for any given voltage to stay at a 0 HW error rate. Whereas in the real world up to 2% is fine and generally more GH / sec can be had up to 2% then just staying at 0% ... without consuming much more power.

If you have cheap power, running them faster may be a good idea too. I pay 7c USD/kWh which I consider cheap enough. Here's how I run my SP20Es:

https://i.imgur.com/7MUDGH1.png

https://i.imgur.com/KNiRWwd.png

Note how I balanced power distribution among the chips. That leads to slightly better efficiency, and cooler running hardware which should keep the rigs alive longer.

yeah all your chips are under the 115 mark for temp which should prevent chip death. at 7 cents you can bump to the 1500 and make a fraction more money then at 1300 gh.  

You also suffer noise since you max fan in a home bad

In a data center so what.

the op did not mention if noise was an issue.



and my power was 770 for 1300 yours was 990 for 1500 at 7 cents  your last 200 gh costs you 220 watts  so you are gaining 13 cents a day or 4 bucks a month .  

big noise gain

The noise isn't an issue for me since I run my miners in my detached garage. I know it isn't a big gain in FIAT, but I try not to pay too much attention to FIAT values. I'm trying to stockpile as much BTC as possible, and my main goal is extracting as much bitcoin as I can from each difficulty. With my power costs, I will only consider downclocking once the miners have made ROI.

well if temps are managed and noise is not an issue your way makes financial sense.