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Hello fellow miners,

I invested into 2x Neptune 1st batch preorder hoping to get the units fast and expected them to break even quickly. Now I'm getting really worried because of fire hazard KnC Neptune introduced into my house! BTW - is your stuff UL certified, this is a must for insurance!

Both units arrived, total of 10 cubes. I was aware of KnC recommendation on power supplies. I went with IBM 835W power supplies, using 1 per cube. There is a separate power supply that drives the motherboards. Each power supply was load tested to ensure that it can do the job. Fun!

I was also aware that PCIe power connector is rated for up to 75W of power. Look on video cards - there is 2 connectors, right? 6 pin each, up to 25W per AWG18 wire. You can draw up to 150W from a single connector, but you have to upgrade to AWG 16 wires. Guys from molex came up with this design and I'm sure they have tested it before they released it to the real world.

Here is my setup:
2 boards, 10 12.0V power supplies 835W under load each, all connected using custom made AWG 16 wires (the pins for AWG16, crimped and then soldered to ensure best possible contact). Actual power draw is around 350-400W per cube, flowing through single PCIe connector! All configs are stock, no overclocking because KnC used cheaper DC/DC convertors hoping to cut costs down (total 8 DC/DC modules per cube, rated at 40A. 50A ones would cost $0.35 more).

Recently 3 out of 10 cubes failed. You probably guessed by now - PCIe connector. It is not rated for such load. Power supplies tripped and shut off the failed cubes as wiring shorted. Power cable connector melted into power socket on the board! I had a lot of fun replacing the socket - there is some kind of extra tough solder used - it took me almost an hour to do 1 socket with my 40W soldering tool. 2 more to go. I'm about to have best weekend ever. 30% failure rate for a "mature" product in 2 month operation.

Should I invest into fire suppression system? This is the most power hungry miner I have at the moment. Worst possible engineering!

KnC: was it really hard to put 2 connectors, next to each other? Or 3? Or 2x8pin ones? I hope you enjoy $0.36 of savings per cube! Take a look on the stuff that intron does - he puts 2 (!) connectors on a board that will draw ~280W. Look at avalon - their original design was not bad at all. Look at metabank - it was great since the day one. Finally - please look into the boards that marto74 develops - he also has open source ava3 design - you could pick up some tricks from his boards!
I also would like to say thank you for SPI cables being short and ugly. It is 2014, we have USB3 and PoE technologies for our disposal, right? There is also a selection of NCU chips available! Is is really hard to develop a firmware that will operate 1 cube over USB - you claim to have a few "skilled" engineers on staff!  RPi board is cheaper than custom BBB and cheaper than that board you managed to put FPGA onto!

Pictures are here (http://imgur.com/ZNnSDWp) and here (http://imgur.com/zcg0sGh)

P.S. I though Jupiter was a failure - no custom design, just a hardcopy from FPGA done by Altera - fastest and cheapest way to claim that you have ASIC. Hardware engineering was horrible - 3 of 4 modules had fans detached during shipping - imagine what would happen if I wouldn't inspect the unit prior to power on? Neptune is even worse - the cube seems solid - this gives false security feeling - mother of all f%#k%ps!

KnC, I see you managed to put a chipart (https://www.kncminer.com/userfiles/image/Titan_chip_logo.jpg) into Titan chip - how long did it actually take you? A month? This is really the only thing you can be proud of - eyecandy. Even BFL was better with their power design!

Pictures. It seems a coincidence you have a significantly higher failure rate than everyone else, and are also using home made cables and connectors which set on fire.

I run everything else on the same cables and same power supplies - it was never a problem before KnC Neptune.

That doesn't automatically make it their fault.

Sure. There is no direct proof of their fault.
They cut corners. They save a ton of money by putting their customers at risk.

so whats best PSU fpr KnC neptunes?

I have a Neptune running fine.

If anything they need better cooling systems to make it not that fricking loud.

That statement right there is contradictory and will get you sued by an aggressive company. You better hope they're not on here.

KnC does however use a significantly higher load on 6-pin PCIE connectors than what they are rated for.
This makes them responsible for any damage occuring from this.

It is really cheap to circumvent these kinds of problems, another 6-pin PCIE or even an 8-pin PCIE would go a long way with regards to safety (and might even improve efficiency by lowering cable losses).


As KnC has previously stated they are not likely to produce another retail product, and my guess is they didn´t care about these issues as their custom DCs (which they are really designing the units for) will
a) underclock the modules to reach even higher efficiency
b) have significantly lower ambient temperatures
c) custom 14AWG wiring.

Sounds like someone on the knc payroll is annoyed.

KNC do cut corners. They didn't bother putting 6 connectors (only 4) on most of the so-called "modular" Jupiter controller board to save a few cents. Which meant their customers were forced to attach their own if they wanted to expand their "modular" miner to include a few more boards, voiding their warranty. These cost about 2 cents each, so it's nothing other than being cheap bastards them only putting on 4.

Plenty of people have spoken about it would be better to have 2 PCI connectors per Neptune board, so volosator is not wrong. People have voided their knc warranty again to attach a second one, which should have been done by kfc if they really wanted to build a good, safe product.

There are plenty of other example of them cutting corners and being cheap bastards in the knc thread.

Wow, they really are cheap

Ok I am overaggerating.
Although I know what you mean, I am convinced that I can go much further in what I say than in real life.
Most people don't have to resources to track me down or find it too much of a hassle for one statement.

Same issue here, they blame the PSU company for poor quality yet they're pushing well above the power spec with a single pci-e auxiliary power port.
I've had 3 Modules catch on fire so far and 2 PSU's burn up all the while KNC acts like nothing is wrong and won't pay me for the burned PSU's or down time due to their failed engineering. BTW they use Standard Terminals....

Here's the spec:

Connector	No. Pins	Std Terminals	HCS Terminals	Plus HCS Terminals
Six Pin	2	192	264	288
Eight Pin	3	288	396	432

Only two +12 V pins are used in the six-pin connector, even though most power supplies include three.
Standard terminals are rated eight amps.
HCS terminals are rated 11 amps.
Plus HCS terminals are rated 12 amps.
All ratings assume Mini-Fit Jr. connectors using 18-gauge wire under standard temperature conditions.

https://imgur.com/a/1mDek#0 (https://imgur.com/a/1mDek#0)

Here is another miner with similar issue.
You actually got lucky, mine is now baked into the socket on the board.
2 more smoked since OP

What power supply did you have?

I know this is an old thread but locally there is an individual getting rid of some Neptunes for cheap.


From what I can tell the source of the melting and fires is NOT related to pulling 300Watts from the 3 +12V wires but from the single terminal correct?

Because there are many GPUs which use >300+ Watts and many power supplies which have split PCIe such as pictured below.

http://i60.tinypic.com/2zxnus5.jpg


So it means that specifications mean that each yellow +12V wire can carry about 100Watts.



But most GPUs have more than one PCIe connector. So if its drawing 300Watts, then 150Watts come out of each terminal since there are 2.

But with the Neptune, its using 300Watts but there is only 1 6pin pcie connector.

http://i62.tinypic.com/30bpxds.jpg

http://i57.tinypic.com/vo634w.jpg




So is there anyway to upgrade the PCIe connector terminal to a higher quality? Since you can easily solder the current one out, or can you someone find room to solder in parallel another PCIe terminal ?

I make custom 16awg PCIe leads and find that they dont get 'cautiously warm' until >280W and 'concerningly warm' until >330W. I imagine >350 you start risking failure.

the common issue is the connector though, not the wires - and its caused when only 4-5 of the 6 pins make a full, tight connection. a bit of a gap will build up a lot of resisance and or send a small spark gap

How much watts do they use? 350W at the wall or from the miner?

~400watt from each cube
~2kw at the wall

14awg is necessary! curious if that ''Y converter'' that knc sent out with their miners uses 14 and 16awg ??? 14awg on the main cable and 16awg on the 2 branches

I have the same problem with pcie connector failing and melting .....does any one know where to get replacement connectors with pins...if I cant unsolder from board I am sure I can find someone local to to that...then solder in new one

If you are from EU, I should have a few hundreds connectors in stock.

If not, search for this one on the usual resellers:
http://www.molex.com/molex/products/datasheet.jsp?part=active/0455580003_PCB_HEADERS.xml

And, depending, on the price, you can also try moddiy, SKU:CO148

http://www.moddiy.com/products/6%252dPin-Graphics-Card-PCIe-Male-Header-Connector-%252d-90%25-Angled-%252d-Black.html

They are quite hard to unsolder, you will need to heat the area around the connectors, and probably add some flux to take them off without damaging the boards. I'm not sure it can be done in a safe manner without a hot air rework station.

appreciate the link...im in nyc area. I have someone who can remove melted connector and put on new one....for about $100usd....so I wont even bother to try myself as I really don't have proper equipment.....he just needed me to get connectors. i'll let you know how it works out. again thanks