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Bitcoin => Mining support => Topic started by: minefarmbuy on November 05, 2018, 12:14:09 AM



Title: APW5 w/ 821x2
Post by: minefarmbuy on November 05, 2018, 12:14:09 AM
Was interested in running two 821's with an APW5.  Spec looks like it should work, but imagine my pdu might be the bottle neck with just 12A outlets.

Looking at a new PDU with 16A outputs but hoping for some advice before the plunge.


Title: Re: APW5 w/ 821x2
Post by: Steamtyme on November 05, 2018, 12:47:19 AM
You would be running close I think.

Just going baseline 2 * 821 = 2400W

So you'd be somewhere between 220-240V to get the PSU up to the 2600W output range.  Going worst case scenario you are pulling nearly 11 amps steady at 220.

I can't remember how the 821's fared with the voltage settings. If you can get the consumption down you would likely be fine.

There are however quite a few used PDU's you could upgrade to for a decent price to avoid a potential failure. Probably best not to push it, and just upgrade the PDU.

https://www.ebay.ca/itm/Dell-6031-Server-PDU-Power-Strip-J542N-Rack-Mount-4-Outlet-C19-208V-30A-L6-30P/292727554129?epid=2264080894&hash=item4427ec0051:g:-PIAAOSwRZdbm9Kw
https://www.ebay.ca/itm/APC-Dell-PDU-AP6031-4-Outlet-C19-200-240V-24A-1U-PDU-5T439/352470636078?hash=item5210e3162e:g:L8YAAOSwzhZbzpVb

I think those may work for you.

Edit here is the testing Hagss did with the voltage offsets in the review thread (https://bitcointalk.org/index.php?topic=2937129.msg30217488#msg30217488).


Title: Re: APW5 w/ 821x2
Post by: minefarmbuy on November 05, 2018, 01:04:06 AM
Thanks Styme.

My biggest concerns are start up draw as I'm looking at a switched pdu. Currently one we can source is with 16A outlets and is in my price range. I want to be able to start and stop these as needed. I run them -2 already but imagine start up draw is considerably more than HF has posted. Maybe I'm wrong?


Title: Re: APW5 w/ 821x2
Post by: Steamtyme on November 05, 2018, 04:16:30 AM
I dont think the power draw at start up is that extreme, can't say I've ever measured.

Just for an idea though it would need to be about 3500 W at 220 volt to trip a 16 amp switch, which is almost a 50% increase.

You could also use the controller to  soft start/stop the miners if you're really concerned.

Edit: Just double checked the specs, does your PSU have enough power connectors? Pretty sure the 821s take 8 a piece, and the psu only has 14.


Title: Re: APW5 w/ 821x2
Post by: minefarmbuy on November 05, 2018, 06:07:45 AM
Looks like the plan killer.

Only 14. thanks for the eyes. I'll have to grab some psu's along with the pdu since ill be retiring the evga's to gpus full time now.



https://www.newegg.com/Product/Product.aspx?Item=N82E16812198016&Description=pcie%20splitter&cm_re=pcie_splitter-_-12-198-016-_-Product

forgot I have a few of these lying around. thoughts? Never used them on an asic before.


Title: Re: APW5 w/ 821x2
Post by: sarcheer on November 05, 2018, 12:57:56 PM
Some APW5's have more than 14, mine have 20 connectors. I've been running 6 821's on 3 APW5's since the first batch of 821's non-stop, no problems at all! Since around mid-July I've been running them with the settings below, 5/6 are running above 11TH/s but consuming around 1080W! Run much cooler with these settings.

Code:
--avalon8-voltage-level -2 --avalon8-voltage-level-offset -2


Title: Re: APW5 w/ 821x2
Post by: Steamtyme on November 05, 2018, 05:32:49 PM
forgot I have a few of these lying around. thoughts? Never used them on an asic before.

Can't say I've ever used them. The concern would be overloading the cable that you are splitting. I'm not sure what wire gauge they are. Might work but probably worth it to pick up another PSU.


Title: Re: APW5 w/ 821x2
Post by: minefarmbuy on November 05, 2018, 06:01:48 PM
Yea, just pulled it out of the box, 14 6-pins.

One is extremely short so would have to use and extension.

Will look into splitters and extensions more.



https://www.newegg.com/Product/Product.aspx?Item=N82E16812706046&Description=6pin%20splitter&cm_re=6pin_splitter-_-12-706-046-_-Product

That was quick. Thoughts on this?



APW5 has 18 AWG cables so the split with the 16 I would imagine would be beneficial. (I did find the female/male version).

Looks like most extension are 18 AWG so any of those should do.


Title: Re: APW5 w/ 821x2
Post by: Bez on November 08, 2018, 05:52:41 AM
Could you just add two more 6-pin connectors to it?  Something similar to this.

https://www.parallelminer.com/product/24-inch-16awg-pcie-to-male-fork-spade-power-cable/ (https://www.parallelminer.com/product/24-inch-16awg-pcie-to-male-fork-spade-power-cable/)


Title: Re: APW5 w/ 821x2
Post by: minefarmbuy on November 08, 2018, 05:57:26 AM
Probably, I did already order the splitter and an extension and will put it on when I have time to watch the miners physically.


Title: Re: APW5 w/ 821x2
Post by: minefarmbuy on November 12, 2018, 02:41:51 AM
Works like a charm with the equipment i ordered. The spade style would have been a better choice though. No need for the extender with the splitters.


Title: Re: APW5 w/ 821x2
Post by: minefarmbuy on December 04, 2018, 04:03:55 PM
One more note don't use a splitter on the top 6pin's of the either board they get pretty warm. I imagine in a warmer climate they would damage.