PSU Puter - ~2L gaming PC build inside an ATX PSU

LegionDD

Cable Smoosher
Original poster
Jan 6, 2020
12
10
Hello everyone,

I have just finished my most compact build yet and am convinced there's no better place to get some feedback on it than here.
My build fits a gaming PC (7th Gen. Intel + 1050 Ti) inside the husk of a dead, standard ATX PSU (outside volume of just 2.16L).

Admittedly I have been inspired originally by Aibohphobias build SFX160.0 thread here. When a PSU with an attractive exterior shell broke down (XFX XTS 460W passively cooled ATX PSU) I saw that as a sign to go ahead and build my own ATX PSU PC.

Fitting a Mini-STX mainboard and a 1050Ti inside the case there was little room for other components. And even the GPU only fit because I modded the stock 2 slot high cooler with a <1 slot low profile CPU cooler (the same one I used for cooling the actual CPU). So sadly only the DC-DC step up converter (to take the 12V from the AC-DC and turn it into 19V for the mainboard) could fit inside the case, the AC-DC PSU is external and provides up to [email protected] in a compact passively cooled package. The 12V are used to power the DC-DC step up converter for the mainboards 19V input and also directly supplies the 12V requirements for the GPU. The AC-DC PSU is actually a bit overpowered, considering the mainboard can handle at most a 65W CPU and the GPU can at most draw 75W (it is powered through PCIe only).
So an even smaller 150W or at most 200W PSU would've done the job as well, but the 350W was a leftover from an older casemod.

The stock GPU cooler was overpowered for the 1050 Ti (as is evident by the fact, that the 1060 mini card uses the exact same cooler), so thermals didn't change at all with the much smaller cooler. An hour of Heaven Benchmark 4.0 showed that between the runs with the stock cooler and the hacked cooler performance didn't change, so I am confident that the solution is adequate.
As you will see in the pictures, the GPU is basically open air, thanks to the generous ventilation holes in the PSUs top cover.

The CPU however sits below the GPU with all the cables and support electronics (DC-DC step up converter to produce the 19V required by the mainboard and a gimmick 1.8"TFT + ESP32 controller to handle the frontpanel duties) installed next to it, it has little room to breathe. One 40mm Noctua fan takes the duty of sucking hot air away from one side of the CPU cooler out the back and another 40mm Noctua is pushing air in from the front, blowing it over the DC-DC PSUs cooler. Surprisingly the CPU remains relatively cool, 30 - 35 C idle and 70 - 80 C under load (no doubt owed to the fact that the Pentium has a mere 51W TDP).

As mentioned, the duties of the frontpanel (power button, etc) are handled by a 1.8" TFT and an ESP32 controller. The front fan grill serves as a touch button, pressing it long enough (see video) will engage the mainboards power button pins and start the PC.

There are still things I want to do. First and foremost is to replace the crudely improvised faceplate with a 3D printed one that will look better.
A new paintjob is also prudent, as the original paint got a bit scratched up during the build process.
Lastly the ESP32 needs more firmware development, so that the display may show status information in the future (ie HDD activity indicator, CPU and GPU statistics/thermals, FPS counter, etc.)

Specs:
ComponentModelDescription
CPUIntel G456051W TDP Pentium; Could be anything up to 65W
RAMDDR4-2133 2x 4GB SO-DIMM8GB Notebook RAM
SSDTeclast 240GBRandom SSD, stripped of its casing (the PCB is about half the size of the SSD case)
PSU12V/30A AC-DC & 12V to 19V DC-DC12V PSU was intended for LED lighting applications; DC-DC step up converter is a generic 150W type
MainboardAsus H110S1Mini-STX with M.2 to PCIe x16 Riser cable
GPUZotac 1050 Ti miniwith a PCB barely longer than the PCIe slot it tightly fits the ATX PSU dimensions
Coolers2x LC-CC-65two low profile CPU coolers cool the CPU as well as the GPU (the original cooler was removed from the GPU and the CPU low profile cooler was modded on - temps didn't change at all compared to stock)
Fans2x Noctua A4x10Two Noctua 40mm fans produce some airflow over the mainboard and DC-DC PSU
CaseXFX XTS 460W modular passively cooled PSU (standard ATX size)The PSU was defective and so I gutted it and put a PC inside
Outside dimensions are: 16cm x 15cm x 9cm => 2.16L

Pictures:













I hope this inspires someone else to push the envelope.
 

ignsvn

Member of the Order of the SFF.N Empire
Moderator
Apr 4, 2016
1,007
819
It doesn't look pretty but it's clearly impressive.

I can't measure it clearly from the picture, but that external AC-DC converter is longer than the case, no?
 

LegionDD

Cable Smoosher
Original poster
Jan 6, 2020
12
10
Thank you, I think.

Yes, the AC-DC PSU is 21.5 cm x 7 cm x 4.5 cm.
 

LegionDD

Cable Smoosher
Original poster
Jan 6, 2020
12
10
SFX-L or bust!
You're saying that as a joke, but I'm already doing research to see if there's any kind of x86 gaming capable hardware (preferably a dedicated GPU - using the UDOO Bolt with its Ryzen1000 and Vega8 iGPU is sort of cheating) that I could fit inside a SFX PSU ;)
 

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
3,370
5,874
I wasn't joking and was thinking the same thing ;)

You could actually (I think) fit the HDPlex 80W AC-DC into the same enclosure and have a fully brickless build.

 
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LegionDD

Cable Smoosher
Original poster
Jan 6, 2020
12
10
I wasn't joking and was thinking the same thing ;)

You could actually (I think) fit the HDPlex 80W AC-DC into the same enclosure and have a fully brickless build.
Only if I leave out the GPU. Sadly I need 12V and 19V. The HDPlex delivers 19V, so I'd need a step down DC-DC to supply power to the [email protected] But this gave me the idea to add current monitoring to the controller, so I can see how much power that system actually needs and then look for an appropriately sized PSU.
Or maybe even design and build one. My guess is, full load I'll need something like 120+W.

In the meantime I'm thinking I'll need to find a way to use a notebook GPU (MXM slot) to have a hope of fitting a gaming system inside a SFX PSU case.
 
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W4RR10R

Cable-Tie Ninja
Bronze Supporter
Jan 29, 2019
181
190
SFX-L or bust!
Only if I leave out the GPU. Sadly I need 12V and 19V. The HDPlex delivers 19V, so I'd need a step down DC-DC to supply power to the [email protected] But this gave me the idea to add current monitoring to the controller, so I can see how much power that system actually needs and then look for an appropriately sized PSU.
Or maybe even design and build one. My guess is, full load I'll need something like 120+W.

In the meantime I'm thinking I'll need to find a way to use a notebook GPU (MXM slot) to have a hope of fitting a gaming system inside a SFX PSU case.
It might actually be possible, You could potentially use use thunderbolt 3 for the dgpu. Thunderbolt can do PCIe 3.0 x4 and provide up to 100W of power. So a gpu you like the PNY GTX 1650 XLR8 has an extremely small pcb and only get power from the pcie slot. That gpu with the new nuc 10 i7 which is 6c/12t boosting to 4.7ghz would definitely be a contender for performance per liter at 1 - 1.1 L


***EDIT***
Did some digging on TB3, it can charge devices at 100W but can only power devices on the bus at 15W.
 
Last edited:

LegionDD

Cable Smoosher
Original poster
Jan 6, 2020
12
10
It might actually be possible, You could potentially use use thunderbolt 3 for the dgpu. Thunderbolt can do PCIe 3.0 x4 and provide up to 100W of power. So a gpu you like the PNY GTX 1650 XLR8 has an extremely small pcb and only get power from the pcie slot. That gpu with the new nuc 10 i7 which is 6c/12t boosting to 4.7ghz would definitely be a contender for performance per liter at 1 - 1.1 L


***EDIT***
Did some digging on TB3, it can charge devices at 100W but can only power devices on the bus at 15W.
A standard SFX PSU is 100mm x 125mm x 63mm
The Problem is more that standard GPUs are too large (even that tiny 1650) to fit inside a standard SFX PSU. But MXM cards (they have to fit inside laptops after all) are much smaller with a more compact connector (especially on the mainboard side). It's just hard to find adapters that are equally compact.

The NUC could potentially fit, if the outside dimensions leave a few mm room for the PCB inside.

In the meantime, my 3D printer is up and running, so I'm designing a better frontpanel cover. I'm also gonna add current measuring capabilities to the controller, so I can determine how much power a PSU actually needs to run this puppy. Scaling down the PSU might even allow me to fit it inside, or at the very least switch to a smaller external power brick, so I can get a few more points on that performance-per-liter challenge. :p
 

aromachi

Caliper Novice
Dec 18, 2019
23
14
Good work!! The cuts on that front panel are a little rough, but without cnc machines it's just so impossible to get nice cuts. I feel your pain. I tried cutting some plexi by hand last year and it just never comes out perfect. Thanks for posting! As soon as my big ATX conks out I might give this a shot.