QuintLeo
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September 04, 2015, 08:48:49 AM |
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If you're losing 10% efficiency by getting those PSUs, why not use the PSUs you already have and use a good volt step down at 95-98% efficiency? Depending on what you have on hand it would be more efficient and more effective?
1) you're not losing that much efficiency. Many of the Meanwells I've seen could be rated as "gold" by ATX standards, even the lower ones are commonly 88%. 2) Haven't found a stepdown YET that's specified to run LONG TERM at the power draw of an S5 per hash board, a couple talk about "higher possible with a bigger heat sink" but no actual spec for that. 3) The PSUs I already have will probably be getting transitioned to running an S7 or three.... I agree that Bitmain seems to be making it more difficult to undervolt than they could.
Side effect of their "keep it cheap" string design, doesn't seem to be deliberate. The old "pencil mod" was about changing an on-board regulator that doesn't exist on their current designs - and was STILL far inferior to Spondoolies methodology. you don't understand my goals.
sound is my issue. I have a 2.4 cent location but I need quiet gear there.
Wish I could find a place with affordable rent and enough power/cooling in Chelan or Douglass counties. Then again, if I had $50k+ to put into this I wouldn't have to worry about the rent as much. 8-O
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I'm no longer legendary just in my own mind! Like something I said? Donations gratefully accepted. LYLnTKvLefz9izJFUvEGQEZzSkz34b3N6U (Litecoin) 1GYbjMTPdCuV7dci3iCUiaRrcNuaiQrVYY (Bitcoin)
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VirosaGITS
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September 04, 2015, 10:06:43 AM |
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I agree that Bitmain seems to be making it more difficult to undervolt than they could.
Side effect of their "keep it cheap" string design, doesn't seem to be deliberate. The old "pencil mod" was about changing an on-board regulator that doesn't exist on their current designs - and was STILL far inferior to Spondoolies methodology. Seem pretty deliberate to me when the hardware design support voltage control but the option get locked in newer firmware, even though if you dig enough you can unlock it again.
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QuintLeo
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September 05, 2015, 09:34:04 AM |
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I agree that Bitmain seems to be making it more difficult to undervolt than they could.
Side effect of their "keep it cheap" string design, doesn't seem to be deliberate. The old "pencil mod" was about changing an on-board regulator that doesn't exist on their current designs - and was STILL far inferior to Spondoolies methodology. Seem pretty deliberate to me when the hardware design support voltage control but the option get locked in newer firmware, even though if you dig enough you can unlock it again. Just where in the hardware for the S5 is "voltage control" supported?
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I'm no longer legendary just in my own mind! Like something I said? Donations gratefully accepted. LYLnTKvLefz9izJFUvEGQEZzSkz34b3N6U (Litecoin) 1GYbjMTPdCuV7dci3iCUiaRrcNuaiQrVYY (Bitcoin)
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RichBC (OP)
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September 05, 2015, 04:40:06 PM |
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Voltage control is achieved by reducing the 12V supply voltage. As the chips are powered in a string, like Christmas Tree lights, this reduces the core voltage to each chip.
Rich
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RichBC (OP)
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September 05, 2015, 06:00:45 PM |
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Looks good Phil, Meanwell seem to have a very big range of PSU's. I picked up, at a price I could not resist last night, 4 x 5V Meanwell PSU's from ebay. Am going to try them in pairs as they should give adjustment from 8.6V to 11.6V. Rich
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QuintLeo
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September 05, 2015, 07:32:44 PM |
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I'm not sure but I think that's the same RSP-320-12 I mentioned as one of my original 2 links, just from Jameco instead of from TRC. (if it's not, then I have changed my mind since then on the "optimal" one as it's the one in my booklinks.) Mouser also carries them, I have noticed, but for a couple bucks more, and at least 1 seller on Amazon in the same price range. I dunno if they have enough isolation to use them in series, DO let us know how that works out.
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I'm no longer legendary just in my own mind! Like something I said? Donations gratefully accepted. LYLnTKvLefz9izJFUvEGQEZzSkz34b3N6U (Litecoin) 1GYbjMTPdCuV7dci3iCUiaRrcNuaiQrVYY (Bitcoin)
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philipma1957
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'The right to privacy matters'
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September 05, 2015, 09:39:53 PM Last edit: September 05, 2015, 09:55:51 PM by philipma1957 |
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I'm not sure but I think that's the same RSP-320-12 I mentioned as one of my original 2 links, just from Jameco instead of from TRC. (if it's not, then I have changed my mind since then on the "optimal" one as it's the one in my booklinks.) Mouser also carries them, I have noticed, but for a couple bucks more, and at least 1 seller on Amazon in the same price range. I dunno if they have enough isolation to use them in series, DO let us know how that works out. all my testing will be on the s-7. I have done a fan mod on the one I have at my house. huge improvement in sound. links to two of these psu's https://i.imgur.com/5JvfR8m.jpghttps://i.imgur.com/kh94dIs.jpghttps://i.imgur.com/2vniinV.jpghttps://i.imgur.com/mMM3ydE.jpghttps://i.imgur.com/jjrUOa4.jpghttps://i.imgur.com/v058Wvk.jpghttps://i.imgur.com/Qc6o4pK.jpghttps://i.imgur.com/lLgxB28.jpghttps://i.imgur.com/vPGNi5W.jpghttps://i.imgur.com/sHBG6GR.jpgI will post a few photos of the fan mod I did a 90 mm noctua fan please cover the ac in or you can kill yourself
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RichBC (OP)
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September 07, 2015, 05:47:12 PM |
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HP DPS-600 / Series ESP135 Model PS-3601-1C - (HP Spares number 338022-001) PSU Test
Ran some tests today on the DPS-600 PSU with a voltage adjust pot.(-12V to the Voltage input pin, Pins 5 to 9) Bottom line not much use with an S5.
The pot allows adjustment from 12.2V to 10.5V. (If adding a pot put a 150 Ohm resistor in series so that that is as low as you can adjust. I think this is how I blew the first PSU?)
Measured the efficiency of the PSU and at 12V it was 82% Good news was that this only reduced to 81% when set to 10.5V
The Bad news is the the output power is significantly reduced when the voltage is reduced. The rated power from 12V is 560W, this reduces to 220W at 10.5V This is unfortunately not quite enough for an S5 with both hash boards connected. I did however test to see what the best with 2 hash boards that could be achieved.
This was at 11.6V and 350Mhz (Yes the S5 does not need 12V at the rated frequency) This consumed 559W at the wall for 1150GH giving 0.486J/GH (with 12V 0.51J/GH)
With a single hash board connected best was. 10.6V and 300MHz which consumed 211W at the wall for 495GH giving 0.426J/GH
So it's not a bad PSU with 80+ efficiency and can be voltage adjusted. However because the possible output power reduces with voltage it unfortunately does not have enough power below 11.6V for the S5.
Rich
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VirosaGITS
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September 07, 2015, 07:47:53 PM |
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Hmm need something better, this is nearly the same as just running the S5 on stock settings on a Platinum or such PSU. Thanks for testing that unit. Maybe two units would work, one per PCB?
At 200w you'd need to go down to 9.5v~ iirc thats around where the power drain is under 200w and is about the same hashrate as a S3.
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flikflak
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September 07, 2015, 08:00:23 PM |
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Wow, thanks for testing that. To have a 0.426J/Gh with an ~80% efficiency PSU is quite something. Also the temperature should drop @ 10.6V (less noise). I think its worth the effort. I will do some testing soon (no time for that at the moment, so in 2 weeks I guess).
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RichBC (OP)
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September 07, 2015, 08:17:17 PM |
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Yes agreed I would need to get down to around 9.5V, trouble is it won't go that low & even if it did there would then be < 200W available as power will continue to fall. So an interesting experiment and good to get some real at the wall numbers with reduced voltage. All my earlier measurements were measured on the input to the miner, so taking no account of PSU efficiency. I am now testing with two 5V PSU's in series, have adjustment from 9V to 12V. Good news is that they work, will be Tomorrow before I have some results. One feaature that holds things back is that on both my S5's one hash board better than the other, so you have to set the voltage for the worse one. At lower voltages seems to be about 0.3V difference for the same error rate. Have not attempted to understand why one is better than the other, but would only take one chip in the chain to upset things. Rich
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RichBC (OP)
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September 07, 2015, 09:26:19 PM Last edit: September 07, 2015, 09:45:51 PM by RichBC |
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Have measured the efficiency of the MeanWell HRP-150-5 5V PSU's with 2 connected in Series. BTW there seem to be no problems connecting them in series although I am being careful to adjust them both to the same voltage. The DC output is isolated from the metal case. Efficiency measured at 81% from 9V to 10V & 83% from 11V to 12V. So a bit lower than the quoted 87%, but I always seem to find that. Could be my measurement technique or perhaps the Manufacturers are a bit generous? Here is the setup with the PSU's connected in series, with some cooling from the Miner exhaust, although they seem to run quite cool without a fan. Will measure the actual temperature they get to at some point. 5V PSU is rated at 70 Deg with a sensor on the Power Stage heatsink. Ambient needs to be below 45 deg for full rating. Measurements of Hash & J/GH to follow. Rich
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SLEI
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September 07, 2015, 10:53:06 PM |
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DPS-600 has a current share pin so You can connect them in parallel to S5. 10.5 V 40A should be enought for undervolted/clocked S5. Small DPS fans stay quiet when power is low and You still have a under 40$ power source. Maxed DPS fans have a very annoying high tone whine.
I have 3 S1 undervolted with DPS-600s as livingroom heaters 40db at 1m.
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VirosaGITS
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September 07, 2015, 11:50:57 PM |
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DPS-600 has a current share pin so You can connect them in parallel to S5. 10.5 V 40A should be enought for undervolted/clocked S5. Small DPS fans stay quiet when power is low and You still have a under 40$ power source. Maxed DPS fans have a very annoying high tone whine.
I have 3 S1 undervolted with DPS-600s as livingroom heaters 40db at 1m.
Like RichBC said (dejavu), at 10.5V it support 200W~, not the full rating from when it's ran at 12V. So you'd need two for a S5. For a S3 and a S1 its plenty.
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SLEI
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September 08, 2015, 12:33:23 AM |
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"Ran some tests today on the DPS-600 PSU with a voltage adjust pot.(-12V to the Voltage input pin, Pins 5 to 9) Bottom line not much use with an S5. "
One is not enought but two is. Quick search from net gave me a price of over 50$ per Mean Well 5V supply and You need at least two of them. Efficience is about same and You can get pair of DPS-600s with wires at 40$. 17$ per DPS-600 shipped; RC servo extensions for on-off pins, trimpots and current share; molex-PCI-E connectors for power feed.
DPS-600 is easy to hack You don't need to open it.
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alh
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September 08, 2015, 05:37:04 AM |
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This is very interesting folks. I wonder if perhaps this will become even more viable with used S5's that should come to market at reduced prices as the S7 roll-out happens. Something like this might well allow an S5 to be "tamed" enough in terms of heat and noise and also efficiency.
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RichBC (OP)
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September 08, 2015, 07:36:12 AM |
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DPS-600 would be fine except that the power drops off with the voltage reduction and will not go low enough in voltage, so have ruled it out as an option for the S5. The Meanwell 5V PSU's I picked up 4 from ebay at only $45 the lot delivered. I have made some measurements with the Meanwell 5V PSU's in series, here are the results. MHz V Core V A W GH J/GH 200 0.69 10.35 260 665 0.391 175 0.66 9.9 210 575 0.365 150 0.65 9.7 175 500 0.350 125 0.64 9.6 147 415 0.354 100 0.63 9.45 119 330 0.361
The efficiency should be better at 100 & 125Mhz but is being held back by the less good Hash board, that needs a higher voltage, particularily as you get near 9.5V. I will make some measurements on the single better hash board at some point. However not bad. Rich
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elrippo
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September 08, 2015, 08:28:46 AM |
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DPS-600 would be fine except that the power drops off with the voltage reduction and will not go low enough in voltage, so have ruled it out as an option for the S5. The Meanwell 5V PSU's I picked up 4 from ebay at only $45 the lot delivered. I have made some measurements with the Meanwell 5V PSU's in series, here are the results. MHz V Core V A W GH J/GH 200 0.69 10.35 260 665 0.391 175 0.66 9.9 210 575 0.365 150 0.65 9.7 175 500 0.350 125 0.64 9.6 147 415 0.354 100 0.63 9.45 119 330 0.361
The efficiency should be better at 100 & 125Mhz but is being held back by the less good Hash board, that needs a higher voltage, particularily as you get near 9.5V. I will make some measurements on the single better hash board at some point. However not bad. Rich Why don´t you take this oneor this oneor this oneor this oneI think these are in your range, or i am mistaken something
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For Advertisement. PM me to discuss.
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RichBC (OP)
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September 08, 2015, 08:41:12 AM |
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Problem with those & most 12V PSU's is that the adjustment range is too small, they only go down to 10.8V. Having 2 x 5V supplies give me the adjustment range I need, also the ones I bought were very chap compared to the ones you have linked to.
Rich
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