Concept Help with power delivery [STX+GPU]

Thehack

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So it's all handled 'on-board' with STX, no pun intended XD Nice analogy, thanks :) So then, the solid state relay is only required when using no psu(DC step down board), or a smaller psu such as a mini that has I guess doesn't have sync capabilities on the pcie?

Does that mean, in theory, the above layout with a Mini in place of the 360 would work?

Yes. You can either:

1. Use the Add2psu. What the Add2psu does is it takes a voltage input (12 or 5v) and makes a connection (PS_on and GND). This means it is an essentially a solid state relay.

2. You can use an off the shelf 12v solid state relay. Use 12v (fan) output from motherboard, and connect the PS_on and GND to the input and output pins on the SSR.

Note, again, this is not 100% guaranteed to work. Sometimes the capacitor discharging when you turn off the pc will cause the on state to loop and never turn off.

The MINI sync output (to talk to Dynamo 360) as designed uses a signal output, instead of a power output like the Add2psu. The signal output doesn't have this problem.

It's complicated but I don't want you to think this will 100% work. I've had a couple reports of it not working when I designed the Distro 400 when using a 12v output from the motherboard.
 
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Ross Siggers

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Right! Okay, so using an Add2psu will make the connection directly through the 24-pin, instead of using a relay. Neater, but the same result?

And when the motherboard switches off, the output to the add2psu will be lost, hence cutting the Mini's 12V that's plugged into the gpu.
 

Thehack

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Right! Okay, so using an Add2psu will make the connection directly through the 24-pin, instead of using a relay. Neater, but the same result?

And when the motherboard switches off, the output to the add2psu will be lost, hence cutting the Mini's 12V that's plugged into the gpu.
Yeah. Pretty much.

AC-DC => motherboard

AC-DC => MINI => Add2psu

AC-DC => MINI => GPU power

STX => Add2psu
 
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Ross Siggers

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Okay cool :thumb:

This is good, at least I know what components and layout I need, to try this out. I will take into account this is not a 100% surefire solution though.

The H110S2 motherboard actually has an lvds connector so you can plug lcd displays to it directly. There's a 2x3 grid of pins in one corner of the board, and depending on the layout of jumpers on these pins, you can change the voltage supplied to the lcd panel. 3v, 5v, or full 12v.

Is this a safe place to pull my signal for the add2psu, or should I use the chassis fan header, which is occupied already?
 

Thehack

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Okay cool :thumb:

This is good, at least I know what components and layout I need, to try this out. I will take into account this is not a 100% surefire solution though.

The H110S2 motherboard actually has an lvds connector so you can plug lcd displays to it directly. There's a 2x3 grid of pins in one corner of the board, and depending on the layout of jumpers on these pins, you can change the voltage supplied to the lcd panel. 3v, 5v, or full 12v.

Is this a safe place to pull my signal for the add2psu, or should I use the chassis fan header, which is occupied already?

I did a quick search and it seems some versions use a contact relay. You'd need a power rail output to power it. I'd used the fan header.
 
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Ross Siggers

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Okay, noted.

Am I getting ahead of myself by asking if another method is to use Sata power from the board, into molex on the add2psu? that has 12v pins right
 

Choidebu

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Didn't you read some posts above..... It's sata3 and not compatible with 3.5 hdds, hence no 12V. Only 5V.

Yeah page 23 of the DeskMini A300 manual.

But idk... could be just the A300... your manual doesn't say anything about it.

Here's what irks me.... you've been asking the same questions since november last year... questions which have been answered. In this thread.

If you got the parts then play with it...
 
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Kmpkt

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Since it's probably relevant here, 19V only for Micro/Mini STX (no 12V-19V wide input). Confirmed by Bill Chen himself.
 

Choidebu

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So... I see you currently have dell brick, which is 19V. So how are you going forward for this? Stick with it or go 12V and get a new (internal?) brick?

The 360 was perfect for this, but yeah if you don't have the space....

PM @aquelito and order some loadswitch from him. But if you stick with 19V you're gonna need to convert that to 12V that the gpu use.

Edit: where in the manual does it say it supports 12V in? I only see 19V
 

Ross Siggers

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Here's what irks me.... you've been asking the same questions since november last year... questions which have been answered. In this thread.

I mean, I suppose with different people chipping in, explaining things different ways, I find it somewhat confusing, but what The Hack said today about how STX boards handle power helped very much. I was initially told that I needed a 360, and then that I could use the Mini, and was subsequently unsure of how to get the signal from a board I didn't think had the capacity to do so...

In the very first post I asked about a pcie-->DC power cable, which I thought was one of the simpler questions. But I ended up finding the(admittedly stupidly simple) pinout and I'm going to make one which should work fine.

I'm sure looking back through the entire thread it would make more sense to me now. But I don't know what to tell you dude. I can't stop you being pissed off at me, if you're frustrated you're welcome to stop contributing? I'm not here to make enemies :/

Since it's probably relevant here, 19V only for Micro/Mini STX (no 12V-19V wide input). Confirmed by Bill Chen himself.

The manual states both 12 and 19v, so I sure hope it's not a typo...
 

Ross Siggers

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Edit: where in the manual does it say it supports 12V in? I only see 19V

Hmm, you're right the pdf says 19v only. But my printed manual clearly states 12v as well, the pdf is a later revision of the document...this could be an issue XD XD
 

Kmpkt

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His is an ASUS board, I'm not sure that all the STX boards are the same.

Sorry if I confused matters, I haven't been following this thread that closely and just assumed it was an AsRock board.
 

Ross Siggers

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Yeah that's awesome @W4RR10R . I hope you don't mind I altered the diagram to show mine :)

I think the last thing that I had wrong in my head, was that I could pass the motherboard power source through the Mini, and use 12v. But that can't be confirmed, and like people have said even if it did support the lower voltage, 19v would be preferred. I saw that @Thehack added a text diagram to one of the previous posts, with two seperate 19v feeds. SO.

here's what I ended up with;



@Kmpkt Regarding the motherboard power, is it okay to use the DC connector that comes with the Mini, and solder on another couple of wires to feed to the motherboard? As long as they're of a suitable gauge. I was going to just put these into a 2.5x5.5 connector that I'll buy :p
 
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