Open Compute WindMill v2 Motherboard

[macrules34]

Build’s Name: Linux Box
Operating System/ Storage Platform: Linux
CPU: Intel Xeon
Motherboard: Quanta Open Compute v2
Chassis: Custom
Drives: TBD
RAM: TBD
Add-in Cards: Video Card
Power Supply: TBD
Other Bits: None

Usage Profile: Will be used as a node for testing.

I was looking at the specs of the pins for the Open Compute WindMill v2 motherboard to back-plane connector. I'm looking to see if all I would need is to apply the 12.5vDC to pins P1 & P2 and ground to pins P3 & P4 to boot the board? Are any of the other pins that I would need to use to run this board? Pin identification is on page 21 of the following manual.

Open Compute WindMill v2 Manual

 

[gigatexal]

those of you co-opting open compute hardware for home labs are real cowboys. I am waiting until someone gets it so understood that I can replace all of my server hardware with O.C stuff. I'm just so used to having power buttons and simple atx connectors and things that just plugin and work like legos

 

[macrules34]

Is the expansion slot on those Quanta motherboards for a raiser card only or is it a 16x PCIe slot as well?

 

[T_Minus]

those of you co-opting open compute hardware for home labs are real cowboys. I am waiting until someone gets it so understood that I can replace all of my server hardware with O.C stuff. I'm just so used to having power buttons and simple atx connectors and things that just plugin and work like legos

Seems like someone here could whip-up some wires / adapters and make a couple bucks supporting the forum members who are like you want to give them a go but don't want to do 'hands on' wiring. I don't know the ins and outs of the OC stuff but maybe a 'plug and play' box/converter/power-supply would be in order, something that can power 1 system/2nodes and another that could do2 system/4nodes ??

 

[macrules34]

The manual shows that there are 4 power pins (2x 12.5vDC and 2x Ground) and then 16 signal pins, I'm not sure if you can just add power to the board and it will power on or if any of those signal pins have anything to do with booting.

 

[gigatexal]

Seems like someone here could whip-up some wires / adapters and make a couple bucks supporting the forum members who are like you want to give them a go but don't want to do 'hands on' wiring. I don't know the ins and outs of the OC stuff but maybe a 'plug and play' box/converter/power-supply would be in order, something that can power 1 system/2nodes and another that could do2 system/4nodes ??

yep, if said wiring was reasonably priced, I would grab an OC box if just to stay up to date on things.

 

[macrules34]

Looks like if you want to buy the connector that is on the mid-plane you need to buy a minimum of 528 pieces, that would coast over $2k. Looks like you may need to solder the wires to the board.

 

[smithse79]

Is the expansion slot on those Quanta motherboards for a raiser card only or is it a 16x PCIe slot as well?

It is a standard 16x PCIE slot. At least a video card works in it.

 

[novegg4]

The manual shows that there are 4 power pins (2x 12.5vDC and 2x Ground) and then 16 signal pins, I'm not sure if you can just add power to the board and it will power on or if any of those signal pins have anything to do with booting.

Tried just connecting 4 power pins - nothing. According to the manual there are couple signal pins that might be important just to power up:

D1 (short pin) MATED_N Input Low active, indicates motherboard is fully mated
D2 MATED_GND_RTN Connected to GND in midplane

or these:

B3 MB_ON Input Indicates that motherboard starts powered on
B4 PSU_PG Output Indicates that PSU 12.5VDC output is ready

Anyone to suggest, please?

 

[s2600gl]

Of those 4 pins the B4 PSU_PG might be worth trying. I suspect the PG stands for Power Good.

PSU:s usually have a Power Good Signal to tell the MB / CPU that the supply voltage is within specs and that
it's safe to start the boot process.

On a standard ATX PSU the PG signal is +5V. Unfortunately I couldn't find any info on the signal level for this board in the manual....

D1, D2 and B3 are probably used by the midplane to decide if it needs to introduce a startup delay or not.

Disclaimer:

These suggestions are based purely on studying the manual.

 

[novegg4]

Of those 4 pins the B4 PSU_PG might be worth trying. I suspect the PG stands for Power Good.

PSU:s usually have a Power Good Signal to tell the MB / CPU that the supply voltage is within specs and that
it's safe to start the boot process.

On a standard ATX PSU the PG signal is +5V. Unfortunately I couldn't find any info on the signal level for this board in the manual....

D1, D2 and B3 are probably used by the midplane to decide if it needs to introduce a startup delay or not.

Disclaimer:

These suggestions are based purely on studying the manual.

Thank you very much. Trying to rent a sample power board from a friend of mine to gather more details.
It sounds like D2 is just connected to global Ground, wondering what "Low Active" means on D1?

 

[s2600gl]

Probably that there's a pull-up on the D1 pin in the midplane so that the circuitry sees a high level when nothing is plugged in.
As soon as you plug in the MB, D1 gets routed either straight or through some circuitry on the MB to the D2 pin and back to ground.

This will pull the D1 pin low on the midplane and indicate that something is plugged in.

 

[gigatexal]

Keep up the good fight guys. This is a fascinating thread

 

[macrules34]

With the adaptations to make these boards run off of 120v by DonJon in the "Potential Deal: 2x Dual 2011 nodes @ $199, Quanta Openrack" thread there must be a way to make these fit in or design a standard 19" rack-mount case.

 

[novegg4]

Probably that there's a pull-up on the D1 pin in the midplane so that the circuitry sees a high level when nothing is plugged in.
As soon as you plug in the MB, D1 gets routed either straight or through some circuitry on the MB to the D2 pin and back to ground.

This will pull the D1 pin low on the midplane and indicate that something is plugged in.

Have had a chance to test it out on the weekend.
Apparently only 3 signal wires are incorporated (at least in the start / post)

D1, D2, B4

B4 is just plain +5V (actually +4.84V), however D1+D2 might be way harder to figure out / substitute.
Do you mind to suggest possible schematics - research direction ?
Measuring up a current D1->D2 might give an idea what the midplane circuitry resistance is about and then just substitute one with a matching passive load = placeholder resistor?

 

[s2600gl]

Were you by any chance able to test boot up by just applying +12.5V to P1/P2, GND to P3/P4 and +5V to B4 ?

I would have thought that D1/D2 is something the midplane needs rather than the MB (seeing as it is an input signal
from the midplanes point-of-view). I.e. at startup the midplane checks D1/D2 on both MB0 and
MB1. If both MBs are present, boot MB0 and start the timer delay before booting MB1. If not, boot whichever MB is seated
immediately.

+12.5V on the P1/P2 gets the VRMs on the MB primed and ready for action, but the +5V on B4 should be the signal that
eventually brings the CPU(s) out of reset.

There's annoyingly little information about the midplane (or I just suck in finding it).

Sigh... I wish I hade one of those puppies to play with (or a dozen)....

 

[gigatexal]

what we need is someone from FB or Google or someone from the opencompute foudnation team to join STH. @Patrick et al., let's reach out to who we know and get them to, um, "join"?

 

[Scott Laird]

Are there docs that are only available to OpenCompute members, or are you looking for someone who knows the hardware to answer a few questions?

 

[macrules34]

What we are trying to determine is how to boot one or more of these motherboards without using the mid-plane. All we have to go off of is the document noted on the first post of this thread.

We know that you can't simply just apply power to the board as novegg4 has already tried this.

 

[novegg4]

Were you by any chance able to test boot up by just applying +12.5V to P1/P2, GND to P3/P4 and +5V to B4 ?

I would have thought that D1/D2 is something the midplane needs rather than the MB (seeing as it is an input signal
from the midplanes point-of-view). I.e. at startup the midplane checks D1/D2 on both MB0 and
MB1. If both MBs are present, boot MB0 and start the timer delay before booting MB1. If not, boot whichever MB is seated
immediately.

+12.5V on the P1/P2 gets the VRMs on the MB primed and ready for action, but the +5V on B4 should be the signal that
eventually brings the CPU(s) out of reset.

There's annoyingly little information about the midplane (or I just suck in finding it).

Sigh... I wish I hade one of those puppies to play with (or a dozen)....

Nope, tried all combinations:

Constant: P1/P2 => +12.5V; P3/P4 => GND all from midplane

Variant 1. B4=>Midplane (D1/D2 disconnected) .............. none
Variant 2. D1/D2=> Midplane (B4 disconnected) ............... none
Variant 3. B4=>5V ATX and D1/D2=> Midplane ......... success

So only two things left to unscramble D1 and D2. Most likely D2 goes to GND
How and where to connect D1 ?

Analogy from arduino pull-up pin connection:

Incorrect:

Correct: