Mini STX + GPU Power Supply

Echochrome3

Minimal Tinkerer
Original poster
Jan 24, 2018
4
3
I recently picked up an Asus H110S1 Mini STX motherboard. I currently have a i3-6100, 8GB of RAM, a NVME drive, and hopefully a Nvidia GTX 1060. Using this adapter "PCIe x1 to M.2 Key A+E Adapter Cable, R51S" on eBay (I'll post a link once I meet the 2 post count requirement), I was able to get a custom M.2 E Key adapter to 1x PCIe for a GPU.

My question is, how do I power the GPU? I can confirm that a GPU will work in this configuration, as I had a GTX 1050 laying around that only ran off of PCIe lane power.

The board runs off of a 120W 19V power brick and I need a 6 pin PCIe power cable for the GPU. Once I introduce two power supplies into the system, how do I make it so they don't fight and power on at the same time?

I have:
19V 120W Silverstone AC to DC Power Supply.
A DC to DC PICOPSU-150-XT
And a Dell D220P-01 12V 18A Power Supply

Dell power supply pinout:


I would only like one power brick going to the system. Could a get a DC to DC boost converter rated to 120W for the motherboard power and then run that off of my Dell power supply, also powering the GPU off of that same 12V? In order for the Dell power supply to function, the sense pin must be shorted. If I wire a rocker switch to the sense pin, will the computer be upset if the power supply is left on while the computer is off, supply 19V to the motherboard and 12V to the GPU? Or is there a way, once I click the PC power button, the power supply is triggered on, powering both the 19V and 12V at the same time. Possibly a relay wired to the power LED pins, so that the initial computer power switch pre-shorts the power supply, with the power status LED connected to a relay maintaining the Dell power supplies power until the computer enters an off state?

Lots of questions here, hopefully, someone can help me get this GPU running!!

Current Rig pictures (Open Air test bench I machined out of aluminum):
 

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
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You're going to need a powered PCIe riser for this as the M.2 slot has far too little power to push the GPU. There are a number of M.2 to PCI x4 risers that have a power connector that will accept either 4 pin molex or SATA power. As an example:

https://www.newegg.com/Product/Prod....2_adapter_pcie_x4-_-9SIA2RP3S20063-_-Product


Once you have one of these, the simplest way to get power to both units would be to use one of my Dynamo 360 units which you can find here:

https://www.sfflab.com/products/dynamo-dc-atx-360w

For this particular use case scenario, you could plug your 19V AC-DC brick into the Dynamo 360's DC_IN plug (12-24V wide input), and then use the included 6 pin to 5.5mm barrel connector cable to pass power to the Mini STX motherboard via the DC_OUT plug. Once this is done, you can then use the SATA header to power your riser (should provide 60W [5A @ 12V]).

Everything you need (with the exception of the riser) should be included in the Dynamo 360 kit. If you wanted to use a beefier brick (ie. Dell 300W AC-DC 19V) and GPU, you could go all the way up to a GTX 1080ti using this solution.

Also if memory serves me correctly, your particular choice of board may only support PCIe x2 which means your graphics performance will take a pretty big hit when compared with the AsRock Mini STX board that has a true x4 M.2 connection.

EDIT:

"With x4 PCI Express 2.0 bandwidth, M.2 supports up to 20Gbit/s data-transfer speeds. It is the perfect choice for an operating system or application drive, making your whole PC or professional apps work as fast as possible."

PCIe 2.0 x4 = PCIe 3.0 x 2 which means you're going to get really poor GPU performance (13% overall loss instead of 4% with PCie 3.0 x4). I'd suggest getting the AsRock H110M deskmini unit if you're serious about this build (sorry for the bad news).

This exact build is one of the major reasons I made my unit. Hope this helps!

KMPKT
 
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Echochrome3

Minimal Tinkerer
Original poster
Jan 24, 2018
4
3
You're going to need a powered PCIe riser for this as the M.2 slot has far too little power to push the GPU. There are a number of M.2 to PCI x4 risers that have a power connector that will accept either 4 pin molex or SATA power. As an example:

Once you have one of these, the simplest way to get power to both units would be to use one of my Dynamo 360 units which you can find here:

For this particular use case scenario, you could plug your 19V AC-DC brick into the Dynamo 360's DC_IN plug (12-24V wide input), and then use the included 6 pin to 5.5mm barrel connector cable to pass power to the Mini STX motherboard via the DC_OUT plug. Once this is done, you can then use the SATA header to power your riser (should provide 60W [5A @ 12V]).

Everything you need (with the exception of the riser) should be included in the Dynamo 360 kit. If you wanted to use a beefier brick (ie. Dell 300W AC-DC 19V) and GPU, you could go all the way up to a GTX 1080ti using this solution.

Also if memory serves me correctly, your particular choice of board may only support PCIe x2 which means your graphics performance will take a pretty big hit when compared with the AsRock Mini STX board that has a true x4 M.2 connection.

EDIT:

"With x4 PCI Express 2.0 bandwidth, M.2 supports up to 20Gbit/s data-transfer speeds. It is the perfect choice for an operating system or application drive, making your whole PC or professional apps work as fast as possible."

PCIe 2.0 x4 = PCIe 3.0 x 2 which means you're going to get really poor GPU performance (13% overall loss instead of 4% with PCie 3.0 x4). I'd suggest getting the AsRock H110M deskmini unit if you're serious about this build (sorry for the bad news).

This exact build is one of the major reasons I made my unit. Hope this helps!

KMPKT
The riser I am using is powered. In terms of GPU performance, I am not too concerned with this, and will be running tests once the system is fully functional to see what the performance hits really are.

So with your PSU, I can input 19V from a power brick and provide the motherboard with the same pass through voltage, while also reducing the voltage and outputting 6 pin 12v power for the GPU?

Do you have a model number for the Dell power supply? Also, your power supply will act like a regular ATX power supply when the computer is powered on and off, switching itself on and off until it gets an on signal from the motherboard?
 

Echochrome3

Minimal Tinkerer
Original poster
Jan 24, 2018
4
3
Check out this thread https://smallformfactor.net/forum/t...llest-gaming-pc-gtx-1050ti-g4600-sfx-mb.6247/

Guy has the same mobo and GPU as you. He also uses that powered M.2 riser. He confirms that the GPU can be powered through the SATA power port and he has never had a problem with it.
Not 100% true. He has the duel Ethernet version and a Nvidia GTX 1050 TI that doesn’t require any external power. I did tests with a Nvidia GTX 1050, which only requires PCIe lane power. I am using the motherboards onboard SATA for powering that. The problem I’m running into is finding a power supply that will power the board and the Nvidia GTX 1060 graphics card that I plan on using. That requires an external 12V 6-pin power cable.
 

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
3,382
5,932
So with your PSU, I can input 19V from a power brick and provide the motherboard with the same pass through voltage, while also reducing the voltage and outputting 6 pin 12v power for the GPU?

Yes. This is the exact intended function of the Dynamo 360 when used as a standalone unit.

Do you have a model number for the Dell power supply?

No I do not, but I strongly recommend buying one straight from Dell. There have been a number of people on these boards that have bought cheaper variants and had worrisome trouble with overheating etc. This unit is commonly ripped off and sold at low ball prices. Buyer beware and you get what you pay for.

Also, your power supply will act like a regular ATX power supply when the computer is powered on and off, switching itself on and off until it gets an on signal from the motherboard?

In most cases the board will do this automatically. In the case that it doesn't, there is a sync cable function whereby you connect the 5V and ground from your fan header to two pins on the Dynamo 360 to enable this function as a workaround. If you end up having to do this let me know. It's somewhat convoluted and will be more clearly outlined once I release the official documentation for the devices. I really am just too lazy to type it all out if I don't have to.

I am using the motherboards onboard SATA for powering that. The problem I’m running into is finding a power supply that will power the board and the Nvidia GTX 1060 graphics card that I plan on using. That requires an external 12V 6-pin power cable.

This is where the Dynamo 360 will help you in providing 6 pin power (6 pin, 8pin, 6+8 pin, 8+8 pin). Also using the onboard SATA header and the M.2 power is pretty shady in my estimation. The M.2 is rated for 10W of power while I believe the SATA will push a maximum of 60W. Considering when working hard the card will pull up to 75W, I'd personally be nervous about frying my motherboard.
 

Echochrome3

Minimal Tinkerer
Original poster
Jan 24, 2018
4
3
Yes. This is the exact intended function of the Dynamo 360 when used as a standalone unit.



No I do not, but I strongly recommend buying one straight from Dell. There have been a number of people on these boards that have bought cheaper variants and had worrisome trouble with overheating etc. This unit is commonly ripped off and sold at low ball prices. Buyer beware and you get what you pay for.



In most cases the board will do this automatically. In the case that it doesn't, there is a sync cable function whereby you connect the 5V and ground from your fan header to two pins on the Dynamo 360 to enable this function as a workaround. If you end up having to do this let me know. It's somewhat convoluted and will be more clearly outlined once I release the official documentation for the devices. I really am just too lazy to type it all out if I don't have to.



This is where the Dynamo 360 will help you in providing 6 pin power (6 pin, 8pin, 6+8 pin, 8+8 pin). Also using the onboard SATA header and the M.2 power is pretty shady in my estimation. The M.2 is rated for 10W of power while I believe the SATA will push a maximum of 60W. Considering when working hard the card will pull up to 75W, I'd personally be nervous about frying my motherboard.
Does the power supply that you're selling come with any cables, or will I have to custom make those for my need?
 

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
3,382
5,932
The Dynamo 360 should include all of the cables you need. The M.2 to PCIe x4 needs to come with its own adapter cable to be able to take SATA power, but this is typically included with these units.