PCIE Meltdown
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- Опубликовано: 20 мар 2024
- Why is there no standard polarity for PCIE power connectors? This cheap PCIE power cable caught me out and killed an Antminer control board.
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Get some terminal extraction tools and swap the pins! Way less work than applying non matching heat shrink. Also check if the the wire is steel with a magnet. I just had to cull a bunch of dupont wires, croc clip leads, and computer wiring adapters for this reason.
I agree. I used to do that all the time. It takes seconds to de-pin a connector like that and re-assemble to your needs
Yeah, I was going to say the same thing. Much easier.
Steel wire? Never seen it in PC applications and I've seen quite a lot of those. Steel connector contacts on the other hand, yeah those are out there.
That should be done in factory. Why the heck final user should mess with polarities and wires? Manufacturers should be punished for this mess. On the other hand, why not sell those as kits? Separate connectors and wires so people can do what they want.
Yes, copper coated steel wire. Granted these were some really cheap Chinese adapter cables, but the wire itself definitely stuck to a magnet. @@stinkycheese804
There is a standard for PCIe power connectors, pins 1-3 (bottom row) Gnd, pins 4-6 (connector row) +12V. This one has been wired as a 6 pin EPS 12V power cable but they have used PCIe connectors as pin 5 is keyed where it should not be for EPS.
It use to be a bit of a trap for novice pc builders/upgraders. I remember decade or so ago a whole pile of cases where people reported PCIe power was plugged into EPS sockets, and the reverse EPS into PCIe, and all the people saying you can't because its keyed different (well you can with force in some cases). Luckily most times it just had a result of smoking wire or psu cutting out, as typically the short is just through the ground.
They even make PCIe to EPS adapters (and probably vice-versa). I think the problem is that the basic design of the connector has just been adapted and reused a bunch and there are only so many ways you can arrange the pins to be keyed to prevent improper installation (especially against a determined installer). EPS was 4 pins, then 8, PCIe was 6 pins then 8, then 6 + 8 and now it's got a dupont cable strapped to it's back... Add to that the crypto miners repurposing/further modifying commodity cables and probably not even using keyed slots and then Aliexpress/eBay sellers not knowing or caring about the differences let alone being able to properly convey it in an English listing. (No shade, just calling out that it would be a difficult thing for anyone to explain in a non-native language.)
@@alanevans4955Not to mention that the engineers at PCIe SIG lost their minds and made a tiny """600W""" connector for GPUs now that keeps melting down.
Just playing with a sharp thin shim in the plug to see if it is possible to take the wires out and swap them over. If I can work out where the barb is, it should be relatively easy.
I'm surprised you didn't simply de-pin the connectors and swap the wires over to suit your needs, seems like the quickest solution.
They looked to be common molex style pins/sockets.
i think it might be the cheap chinese thing being flipped, not the antminer. take a look at "PCIE Supplemental Power plug pinout" and you'll see that black is always top as per standard on 6 and 8 pin PCIE plugs. what you likely got was EPS 12V extenders being listed as PCIE.
You should get a pair of external circlip pliers for removing the board, when you squeeze, the tips spread apart
I remember learning about P8 and P9 on AT power supplies back in high school. Good thing I went to school before tearing down my own computer for the first time :D
What’s the return on investment in the antminers?
I’m completely new to miners
I've almost fried a graphics card by using some 6 to 8 pin (or the other way around) adapter cable that matched the socket perfectly. Something seemed not quite right and I decided to measure what goes where and lo and behold 12V was shorted to ground....
Not a so uncommon occurrence, a lot of people only pick up that there is a problem when their newly built rig doesn't power on or only powers on without the PCIe 6 / 8-pin plugged in. Turns out the short circuit protection of the PSU has been saving them the whole time.
Why did you place the new connector at the end by cutting off one connector? If you did cut the cable in the middle you could make the double amount of new cables
I only need the plug - the socket is not needed.
thought you are over the whole mining thing 😮
I'm shocked youhaven't got a texas reflow rig aha
Have you let the magic blue smoke out ?😞
Just repin the sockets instead of cutting them off?
Murphy law strikes again
PCIe power connectors do have a standard polarity, I don't believe there's a requirement for which cable color is what though, and the cable would've worked fine without modification as the colors were swapped on both connectors. Instead of adding the heatshrink you also could just remove the pins from the connector and swap them around to match.
I looked into removing the pins from the connector housing, but the barbs appear to be locked into grooves which makes it very difficult to retract them without damage. Perhaps there's a special tool.
@@JulianIlett Aliexpress has the tools, very cheap
@@JulianIlett You can find a tool for this, usually sold under names like ATX Pin Removal Tool for around two pounds from the usual suspects, but in a pinch something thin like a staple should also be able to do it
Tried the staple idea, and eventually got a pin out, but incredibly faffy, so I think I'll buy the proper tool.
That yellow and black motherboard power supply cable is about the only decent quality wire I can get my hands on and I've just got 12 volt fixated in my head when I see it.
What about a male female inline protection cable with Schottky diode?
To make 11V out of 12V???
@@kyoudaiken That's the question, the 12V rail will likely be just over 12V, the voltage drop will be under 1V typically 0.3V for Schottky, in any case I'm thinking Julian's ant miners would run ok at 11V?
Perhaps there are other options that don't have any voltage drop, such as a relay that switches in the full supply if polarity checks ok, or a "zero loss" MOSFET circuit, there are plenty online?
@@dav1dbone The option is: Don't buy dodgy cables or double check the polarity. Much cheaper, much easier.
If the cable is wired up wrong then reverse polarity protection in the cable wouldn't do anything.
If you add reverse polarity protection you still have to make sure that from that point onward* the polarity is right, and double checking would have avoided the disaster anyways.
(*: "that point onward" in this case meaning pcie connector and the controller board it would only help against reverse polarity on the XT60 connector which can't be reversed anyways)
So all in all there is no point adding a reverse polarity protection to a circuit that will only be wired up once and once that's done it won't be reversible anyways.
@@dav1dbone11 Volts is below the ATX threshold for "power OK". And most likely, theye miners use the same standards because they are royalty free and already there.
Where are the fuses? The fuse should have blown long before the wire started melting. That was very close to starting a fire.
in ATX cables, there's no fuse. though, each XT60 least should have at least a 20A fuse on it. automotive fuses would be fine since it's direct feed 12V.