Supermicro Power Question

[T_Minus]

Between my two bins of power adapters I don't have 1 molex to 8pin EPS but I sure did find 5 extensions

Question Now Is:

Will any SuperMicro Yellow cables + black cables work for making my own 8-Pin EPS? I can take one of the female pieces off the extension and make a row of black, and row of yellow.

Is this correct for EPS 8-Pin?
http://www.overclockers.com/forums/attachment.php?attachmentid=117031&d=1349959547

Only 12V and Grnd?

 

[T_Minus]

According to the manual, and picture above that's correct.
Pins 1-4 = Ground
Pins 5-8 = + 12V

So now the question is are the Yellow/Green wires for GFX cards in this case +12v like standard yellow cables?

 

[nj47]

Between my two bins of power adapters I don't have 1 molex to 8pin EPS but I sure did find 5 extensions

Question Now Is:

Will any SuperMicro Yellow cables + black cables work for making my own 8-Pin EPS? I can take one of the female pieces off the extension and make a row of black, and row of yellow.

Is this correct for EPS 8-Pin?
http://www.overclockers.com/forums/attachment.php?attachmentid=117031&d=1349959547

Only 12V and Grnd?

Yes, that is the correct pinout. For a good comparison between similar connectors, I think this has a pretty good description of each: All about the various PC power supply cables and connectors.

So now the question is are the Yellow/Green wires for GFX cards in this case +12v like standard yellow cables?

I've taken apart a number of PSU's - and what I've seen is that PSU's with multiple 12V rails distinguish which rail a wire is connected to with the presence of a colored stripe on the yellow wire

 

[T_Minus]

Thanks!

I'm really really perplexed as to why this chassis has the wrong pinout for the 8-Pin EPS. The cable is EXACTLY the right length to go into the 2nd 8Pin EPS plug but the plugs are different, the yellow/12v and black/grnd are in the RIGHT spot though!!

Link To Chassis & Original Investigation: SuperMicro 835 ?

 

[nj47]

Thanks!

I'm really really perplexed as to why this chassis has the wrong pinout for the 8-Pin EPS. The cable is EXACTLY the right length to go into the 2nd 8Pin EPS plug but the plugs are different, the yellow/12v and black/grnd are in the RIGHT spot though!!

Link To Chassis & Original Investigation: SuperMicro 835 ?

One thing I dislike about supermicro is they really aren't shy about using non-standards parts. I suspect what you are looking at may be something similar to the connector described here: PSU for server motherboard

 

[T_Minus]

I have a picture of it someplace, I thought it was in my other thread but I don't see it there now. I'll get it posted here in a couple minutes.

What's really really odd is this is the only SC835 I can find with the narrow power supplies so it can fit this huge motherboard (X10DRX), which is listed as one of the few motherboards supported by this chassis. However, it's listed as a storage chassis but there are a bunch of GPU power cables in there which isn't exactly a storage chassis usage so I'm thinking I may have a sub-set of the SC835 for storage that they did at one point for GPU. I was hoping to find that via Google and find some adapter cables, no such luck and my chassis part # returns 0 results.

P/N: CSE-835
Factory Code: ABC-03

 

[T_Minus]

One side of the 2x 4-Pin matches up with the 4-Pin extension I have, the other 4-pin doesn't match up with the 4-pin extension or the 8-Pin motherboard EPS.

Here's a bunch of pics.

Maybe there's some special adapter for the other 4-Pin that makes it an 8-Pin, and you're supposed to use an extension depending which motherboard?

 

[T_Minus]

Took plastic cover off that covers PDB and that part#: PDB-PT8358824
Hoping to find a Manual on that to see what exactly the "Motherboard ONly" connection is for specifically and why it doesn't align with the proper EPS. Maybe this chassis came with cables I can't find mentioned in the manual or Parts List on their site.

I did find this on CompSource site "INPUT +12V & +5VSB & STANDARD 24PIN OUTPUT W/ 4GPU SUPPORT"

So it's def. a GPU not Storage platform based chassis.

 

[T_Minus]

When looking at motherboard manual page:
SC835XTQ-R982B | 3U | Chassis | Products | Super Micro Computer, Inc.

They list the PDB I have, and it even says there: Input +12V and +5Vsb and standard 24Pin output with 4GPU support!

This is crazy. Listed as storage chassis, then it has 4GPU support and not the proper connections!

http://www.supermicro.com/products/nfo/files/power_supply/psu_cablelist.pdf

Shows it only having 1x 8 Pin!

 

[T_Minus]

So it has only 1 8 pin, 0 4 pin, and then it has a 4+4 8pin that's NOT the EPS 8Pin.

I'm going to have to e-mail SM and see what their intended cables are, they're not listed as extras.

 

[fractal]

Do you have a volt meter?

Do you have a pin pusher?

Do you have confidence in yourself?

If yes to all three, take a working system and measure the volts on the 8 pin eps12v and compare to the spec. This step is not necessary to make it work, but it sure helps with the confidence step. Repeat until you feel you know which pins should be 12v and which pins should be ground.

Use your pin pusher to remove the pins from the non-standard plug.

Use your pin pusher to remove the pins from the extender.

Shove the pins you removed from the non-standard plug into the now-empty housing you took off the extender.

Measure the volts on your newly created 8 pin eps12v plug.

Measure them again.

Assemble your system.

Have a beverage of choice


--EDIT: Before you do that, is there a 4 pin EPS12v plug available? If so, use it for the second CPU. Several of the dual processor supermicro systems I have bought power it that way. The manuals you linked in the other thread suggest there is a 4 pin in addition to the 8 pin.

 

[T_Minus]

There are 2x 8 PIN and 1x 4 Pin, according to manual all 3 need to be plugged in.

On other SM boards I have (V1/v2 specifically) they are optional, this board doesn't say that though.

I've got an e-mail into SuperMicro to see if there's an adapter they make that's not listed that would work

 

[T_Minus]

Supermicro replied back and said the motherboard and chassis are not meant to be used for 'storage' but it would work for that. I kindly pointed them to their own site that displays this in bold and red font However, he did state the 8-pin should line-up for the 12v EPS plug on my motherboard. Per their request I've sent pictures showing the connection and how/why it doesn't work.

@fractal -- With yellow being 12v and black being ground I'll be likely just swap the 4-pin connection, I'm digging through my wires to try to find one with wires doubled up so I can also feed the aux. 4-pin 12v without having to use any molex or additional power for the motherboard leaving the rest for the NVME drives. In the end i'll likely have to convert some of those GPU power plugs to be used for the NVME drives. We will see how many I can cram in there.

 

[T_Minus]

Supermicro response:
- Yes, they are different designed plug / fitting.
- Push it in hard, line it up properly.

I did that, and they went in but there was resistance.

Awaiting a reply about why they're like this and not actually 8-pin EPS 12v standard design.

In one of their (SM) provided images they were using the Yellow+Green Stripe as a 12V on another EPS connection so that must be the other rail on the PSU as was mentioned previously. I will verify with SM after I figure out why this 8-pin isn't correct

 

[T_Minus]

SM Reply: Oval fits in Square, not other way around.

 

[Terry Kennedy]

Awaiting a reply about why they're like this and not actually 8-pin EPS 12v standard design.

On the SC836 with the PDB-824-blahblah distribution board, the "Connect to motherboard only" pair of 4-pins fits into the second EPS12V socket on the X8DTH-iF just fine.

I performed some "minor" work on the PDB cables:

However, as I said in my article, you really don't want to do this if you don't have the right tooling and a real power supply tester - it is very easy to let the "magic smoke" out of some expensive parts.

These are the Digi-Key part numbers and prices (a year old) for all of the parts you should need. Note that this list also has the part numbers for the 6+2 PCIe connector, so don't just blindly order everything.

 

[Tom5051]

If you can solder, I wouldn't bother with the extensions and the crimpers. $130 seems pretty steep for 1 tool.

 

[Terry Kennedy]

If you can solder, I wouldn't bother with the extensions and the crimpers. $130 seems pretty steep for 1 tool.

You really don't want to try to cut corners on these high-current connectors (which is why I listed Molex parts and not generic imports). With soldering you can get a bad connection (particularly if you don't solder regularly) and it is easy to put too much solder on a pin, so it either flows down into the contact area or blobs up and you have trouble putting the pin into the connector shell. Also, you'll never get a good grip on the insulation retention ring with solder - you'll either melt the insulation or you'll try to get a good grip using needlenose pliers (and fail). Not to mention, you need the insertion / extraction tool if you want to get the pins out of an old connector (if you're just changing the shell) without damaging them.

In the late 70's / early 80's the US military did a study on connector reliability. The particular connector studied was the D-subminiature, but the information is applicable to a wide range of connectors. They found that soldered connections were the most reliable if performed by the manufacturer or a qualified depot facility, but that crimp was far more reliable for field terminations. They actually had AMP develop a special pin for field terminations which used a "crush-on-wire" whole-body pin crimp rather than the standard U-fold crimp. They also used a special glass-reinforced connector body instead of the regular thermoplastic. Going even further afield, do you remember the Souriau solder-cup D-sub connectors with the brown plastic that gave off poisonous fumes when heated? [As you may be able to tell, I've been doing this for a while. ]

 

[T_Minus]

It's installed now even though it wasn't technically the right connectors but they did fit as they said it would.
I still need to swap the ram to the 32GB DIMMs and get the SATAdoms in and test her out!

@Terry Kennedy thanks for all that detailed info. I actually have the handful of hand tools to take them apart / put them together. While waiting for SM reply I took apart one of the extensions so I could swap the 2x 4pin to the correct 8 pin EPS but turns out now I don't need too

Now, what's stupid expensive are the plugs/tools/pins/etc for doing a custom wiring harness for my 6L LS engine swap deutsch connectors are not cheap but quality rarely is! No weather-pak connections going on here. Although for the price of the tool and pieces I'm still throwing around the idea of just buying a pre-made harness... LOL! NEW! from Wirecare- Deutsch DT Series BLACK Installer Kit with HDT-48-00 Crimper | eBay

I'm not using any extensions, just converting molex to 4pin 12v per-SM specifications. I debated using a clip-on because the 4-pin 12v wires don't seem too heavy duty but seems a bit 'dirty'. If I was going to do it right I'd pull out some pins on the EPS 8 pin and double-up the wires to the 4-pin but that seems wrong too... I mean why wouldn't SM just + the 8 if that was sufficient for the current.. so molex to 4pin it is.

 

[Terry Kennedy]

Now, what's stupid expensive are the plugs/tools/pins/etc for doing a custom wiring harness for my 6L LS engine swap deutsch connectors are not cheap but quality rarely is! No weather-pak connections going on here. Although for the price of the tool and pieces I'm still throwing around the idea of just buying a pre-made harness... LOL! NEW! from Wirecare- Deutsch DT Series BLACK Installer Kit with HDT-48-00 Crimper | eBay

Don't get me started. I had an Ariel Atom with a GM Racing (300HP) LSJ. That was mostly Weatherpak. The engine was put together with a combination of imperial and metric hardware (not to mention some parts being marked Saab). The biggest problem with that engine was the Heat-on M62. The Harrop 1320 was a much better unit, but didn't completely solve the heat soak issue.

I'm not using any extensions, just converting molex to 4pin 12v per-SM specifications. I debated using a clip-on because the 4-pin 12v wires don't seem too heavy duty but seems a bit 'dirty'. If I was going to do it right I'd pull out some pins on the EPS 8 pin and double-up the wires to the 4-pin but that seems wrong too... I mean why wouldn't SM just + the 8 if that was sufficient for the current.. so molex to 4pin it is.

You got me interested enough to pull one down and look. It is a PDB-PT826-8824 and all of the wires (except for the ATX sense lines, etc.) is #16 - the main ATX, the EPS12V, and the 2 * 4-pin "motherboard only" connectors.

I also examined the pins and there should be no interference when inserting these. I'll label the pins (when looking at the connector end on the cable, with the release tab up) as U (for U-shaped) or S for square. The EPS12V is:

USSU
SUUS

while the pair of "motherboard only" is:

USUU
SUUU

Since the U's will fit in the square holes, these should drop right in, unless you have the 2 halves in the wrong order (which would have one cable square trying to go into a motherboard U on each connector).