KNC cubes power supply

[zekarsalih]

Guys,

I can get my hands on some KNC neptune miners. They are not even used, every cube uses around 275 watt, one set includes 5 cubes @ around 1500WATT.

Price: 700 USD per set
Kwh; 0.03 usd
Rent; 0
Tempreture; -5 in winters  30 Celcius in Summers, I have acces to good cooling though.

I wonder if I can use a power supply of 400 watt for every cube, would that effect efficiency? What is the best power supply to use?

Any one has experience with neptune? picures? please share!

Regards,

[zekarsalih]

  no one ?

[Tupsu]

Wrong,  every NEPTUNE cube uses around 380 watt- 420  watt

Use EVGA G2 1300W -3 cubes or
Corsair RM 850 , RM1000 for 2 cubes.

[zekarsalih]

Thanks,

What if I use 500 Watt PSU for every single cube?
would that change efficiency of them in any way?

[bgibso01]

I've been using 3 corsair 850s and works fine.  You can down clock them and get some decent numbers (.55w/gh).  These things are very finicky to get setup and running.  You will want to tweak each die in order to get the best results.  Also unless you are using custom made adapters, use the Y-cables to attach 2 pci-e cables to each cube.  One cable is usually not thick enough for running that many watts through it.

Also, for the long haul you might look at a server psu to bring down the cost and boost efficiency.

[sidehack]

I've got some pretty good 2KW PSU kits which could handle a Neptune readily.

However, I have never and will never recommend anyone actually buy and run a Neptune - at least not at stock settings. The power draw through their SINGLE PCIE connector is on par with (if not higher than) the power draw for an entire S3 which uses 4 PCIe connectors. It's quite frankly a fire hazard, and the only way to run it with any semblance of reliability is to downclock it to under 300W per Cube. Preferably under 270W.

[fullzero]

Wrong,  every NEPTUNE cube uses around 380 watt- 420  watt

Use EVGA G2 1300W -3 cubes or
Corsair RM 850 , RM1000 for 2 cubes.

I agree.  If using the Corsair RM 850 make sure you use 2x actual pcie cable connectors per cube: so 4x pcie cables; 2x to each cube using the splitter. 

Note these only come with 3x pcie cables (they split into 2x 8 pin pcie each but you obviously only want to use 1x and ignore the branch).  You can get more from corsair direct or from fellow members  (I think I have a few extra of these).  If done in this way I have had no issue running Neptune's with RM 850's. 

If sound isn't a concern; I would go with one of sidehack's monster server PSU's.

[Finksy]

The PSUs and breakout boards in my sig are rated to 2880W, requiring 240V. I would suggest going with a server PSU either from me (J4bberwock's design) or sidehack over multiple off-the-shelf ATX PSU's.

I have an option of 36" 1.5mm² copper cables by J4bberwock, which are slightly larger than 16 awg, and use high quality connectors/pins. They are about as good as it gets for single PCI cable load capacity.  Be very careful with the Neptunes, and do not use poor quality components (including cheap ATX PSU's with thin wiring).

[zekarsalih]

ok, thank you guys first of all.

I have to reconsider if I will be using KNC neptunes since all your replies concern me and I don't like to take a chanse that they burn out my appartment.

1THS Bitmine Coincraft Desktopseries, what is your opinion on those? They are plug to play, since I am not that technical.
Would those suit me better?
They use a lot of electricity as in, they are unefficient. Would that efffect me a lot with 0.03 cent electricity?

How much would it cost me to get the KNC neptunes up and running if I do not have any PSU's and where can I purchase?

[bgibso01]

ok, thank you guys first of all.

I have to reconsider if I will be using KNC neptunes since all your replies concern me and I don't like to take a chanse that they burn out my appartment.

1THS Bitmine Coincraft Desktopseries, what is your opinion on those? They are plug to play, since I am not that technical.
Would those suit me better?
They use a lot of electricity as in, they are unefficient. Would that efffect me a lot with 0.03 cent electricity?

How much would it cost me to get the KNC neptunes up and running if I do not have any PSU's and where can I purchase?

I understand Sidehack's concern and it is legitimate.  BUT, if you use the Y-cables and 2 pci-e cables to each cube you should be ok.  I've been running mine for a bit now and no warmth on the cables.  Once they are up and running, they are the quietest thing out there right now.  I've got 6 running off of one controller using 1700w for 4Th.  I'm also using 240v and not all dies are at stock speed.  Some are lower to keep them cooler.

[zekarsalih]

Thank you BG, that sounds somewhat more possitive. They are so cheap at the moment.. I love to purchase a couple sets since they are much more efficient than the other 1TH miners that are for sale here.

chek your private message please

Regards,

[sidehack]

My concern is more about the ratings on the PCIe connectors and pins than the wire of the cables. The PCIe connector on the Neptune might have 11A-rated pins, but most any cable will have 9A pins on it. Asking 11A (12V 400W across three wires) through a pin rated for a 9A maximum is pretty stupid. If one of those pins has a bad connection it'll force more current into the other two, sending it from 22% over max rating to as high as 80% over max rating (at which point resistive power loss [heat] is 3.3 times as much as at maximum rated current).

I had a hosting customer ask if I'd host a Neptune for him, and the only way I was going to do it was put it on my fireproof Prisma shelving with a thermal fuse wire over every connector that would automatically kill the PSU if it started burning. Even then it was iffy and I'm glad he didn't send it.