Actively Cooled HDPlex 300W AC-DC adapter

royalba94

Airflow Optimizer
Original poster
AVAENTUM SLEEVING
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Apr 2, 2017
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Avaentum.com
My third time writing this up due to my browser thinking backspace meant to go back in history when I was clearly typing...

Background/Motivation:

As I'm sure many of us know HDPlex has recently launched the upgrade/replacement to their 300w DC-ATX unit in the form of the gorgeously heatsinked, higher capacity HDPlex 400w DC-ATX unit. While the new design and higher rating are very welcome things there is a bit of a conundrum in the fact that there seem to be now 400w AC-DC power bricks available to power it. This fact has been brought up a few times in the HDPLEX 400W DC-ATX thread and one comment in particular caught my attention:

The guys at HD PLEX told me that if you push "Active air flow" to the 300W AC-DC brick they have, it will support 400w.

This combined with @Reldey kindly reaching to me a bit later to craft some cables that would allow him to connect the AC-DC adapter to his HDPlex (in the beautiful S4 Mini by @Josh | NFC) as well as passing through the PWM connection from his mobo to a fan on the adapter, led to the creation of this project.

Project History until now:

The first idea was to use a 10pin DIN or 'aviation' plug in place of the usual barrel connector that way all 6pins of the DC output of the unit could be passed into the HDPlex 400w inside the case as well as the 4pins for a PWM extension from a fan mounted to the AC-DC unit all the way to the motherboard.
Realizing that this would create more cabling complexity in the S4 Mini I recommended that we find a way to power the fan directly from the adapter itself. After some searching I found a small Step-Down (or buck) converter that would allow me to take the 19v output of the AC-DC unit and convert it into a more suitable voltage for powering a fan.
The next modification was the decision to use two fans on the unit instead of one: a 20mm one (this nice Noiseblocker one more specifically) for intake on the Output side and then another 10mm fan (undecided currently, probably this one with a gasket) as an exhaust on the top above the AC-in side.
Finally the most recent addition to the list is a way to control the speed of the fan via a 3-4 way switch (or similar) that way they can be tuned (i.e. High - Med - Low - Off) based on your needs.
(mocked up in sketchup because that what I'm most familiar with and 3D warehouse)
__________________

Notes:
  • very rough design, my next step is to move it over to proper CAD (Fusion 360 or Inventor) so that I can model it more exactly and better suited for 3D printing.
  • The mockup shows the Buck converter being placed in the ramp/adapter section but as soon as I took the screenshots I realized that a better place would be the top next to the exhaust fan.


Current Status:

So the part you've all been waiting for... (or just skipped to ;)) the pictures!

Here are the screenshots of the design in it's current state:



Notes:
  • Since I decided to place the Buck converters on the top I went ahead and designed a top to house them and the fans internally to the unit to keep things clean and protected.
  • Need to find a good switch for the speed control of the fans and add the spot for it to the model.
  • I'm considering adding on another part to the AC-input side to house the extra cable and attach the socket for the AC power cord as well.
  • I might also need to change the top design to make room for the original DC-output cables to be internal so that they don't show. Might be a bit of a tall order tho because of the large 6pin connector.
  • I do need to figure out the screws used originally and which ones I'll use for the DC-out mounting plate. Probably will have to wait until my own unit arrives to find out tho.
  • Updated measurements of the current design will be edited in later :)

To-Do List:

This is where I will list out my next steps in the progression of this project.
  • Convert the design to proper CAD I am now using Fusion 360! :)
    • Accurately model and measure the original AC-DC unit
    • Create/find fan, fan grill, gasket, and Buck converter models Not really needed
    • Create v0.3 of the design with the converter/switch up top
  • Figure out if Switch for fan modes can be integrated
    • May need to design my own PCB Too much work lol
    • Decide how many converters and what volts to set them at
    • Find a good & small switch
  • Make Documentation
    • Create Wiring diagram
    • Create Bill of Materials
  • (Acquire unit for myself?) Bought one! Should be on its way to me shortly :)
  • Prototype
  • Test, test, test!

Feedback:

I love feedback so please let me know what you think!

If you have ideas about a better layout for this post please let me know as well. Thx!!​


Notes about plans for this mod:
Assuming all goes according to plan and this mod actually is succesful in raising the wattage output capacity of the HDPlex 300w AC-DC unit I would love to be able to provide Mod-Kits to those who would wish to buy one. I am documenting the process here for the opportunity for feedback and in case someone wants to copy the mods that were done for their own use.

Since that is my hope I am trying to make this mod as plug & play as I can for quick and simple installation. I would love and welcome any feedback about the design and idea.
 
Last edited:

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
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I believe there is a hard OCP at 400W. What I think that means is that even with active cooling, if you try to put together a system that is rated for close to 400W and spikes above that you are probably going to run into almost immediate system shutdowns.
 

royalba94

Airflow Optimizer
Original poster
AVAENTUM SLEEVING
Bronze Supporter
Apr 2, 2017
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Water cool it! ( Jk :) ) awesome project, how do you plan to test it once it's done? I'd love to see how far it can go.

lol and thanks :D

I'm not really sure about the testing just yet, @Reldey has been doing some testing with it but as I currently don't have one I haven't been able to run any tests myself. I'll probably be picking up a used one (if anyone here has an extra) or just ordering a new one soon so I can see what we get.​

How long will it be after the mod? I am super interested in this.

Currently, including the mods, the unit is 200mm x 62mm x 58mm. That is assuming the models are reasonably accurate of course, more final dimensions can be given once I change it over to a proper CAD and double-check the measurements of the adapter.​

I believe there is a hard OCP at 400W. What I think that means is that even with active cooling, if you try to put together a system that is rated for close to 400W and spikes above that you are probably going to run into almost immediate system shutdowns.

Yes, I was thinking about this as well. I'll definitely be wanting to test it more completely to see if that is the case. If it is I'd be interested to see if there is anything that could be done to bump it up just a bit more. I will confess to not being an electrical engineer though so we'll see what happens I guess :)


Thank you all for your comments! I hope to make more progress on the design very soon :)
 

Reldey

Master of Cramming
Feb 14, 2017
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405
What has me really excited about this project, is how much smaller the HDPlex ACDC is compared to the Dell brick, even with the proposed mods. It can also become much more powerful just given some active cooling. I currently have a noctua 40mmx10mm fan attached to the lid with twist ties, and it is performing great. I think adding a second fan will help it perform even better, and I look forward to trying out the 3D printed parts.
 

msystems

Airflow Optimizer
Apr 28, 2017
280
440
I did a lot of performance testing today to see how this brick did over 300 watts. 320 watts was frequently observed and the maximum spike I observed on the wall meter was 335 watts. I had a fan cooling it. None of these tests crashed the system.

Getting above 320 watts was the point where my graphics card driver was crashing frequently on the GTX 1080. Presumably there were higher spikes which were not observable from the slow polling rate of the wall meter.
 

msystems

Airflow Optimizer
Apr 28, 2017
280
440
It was a 120mm fan placed over the top blowing down. A noiseblocker M12-2. I don't know if the brick can go higher, but I wanted to confirm that a 320 average draw seemed doable at least. Those are just my results, I wouldn't draw any conclusions quite yet. I had no way to observe the actual power spikes. I think it takes an oscilloscope for that.
 

msystems

Airflow Optimizer
Apr 28, 2017
280
440
I have a follow up post about the hdplex efficiency. I could be wrong, as this is a crude test, but I believe the efficiency of the combined ac/dc and DC/atx to be pretty poor. I'm not sure the efficiency of each, just both together.

In my tests I was seeing peak power usage at the wall at 320 watts during the heaviest part of benchmark. I kept maxing out the power, so I switched to my enermax revolution 650 sfx. Now this is where it gets interesting.

I put in a heavier processor OC +100mhz, unlocked 2 cores I had disabled, and increased voltage. So now I went to windows to run tests expecting to see 330-340 watts based on my bigger OC.

But the peak power usage with enermax was only 305 watts or so. This enermax psu is about 92% efficient right in the middle of the power curve.

I can't math right now So let's just say the enermax is wasting 30 watts and actual power usage is 275 watts.

That means the HD plex would be wasting 55+ watts.

So combined, I think their efficiency at Max load is high 70% to mid 80%. I don't think it's possible to pull an actual 300 watts of usable power out of these.
 

Reldey

Master of Cramming
Feb 14, 2017
387
405
And yet, here is the weird thing. Even though this combo is less power efficient than other solutions, this is the one combo that has reduced the coil whine I experience from my GTX 1080 the most compared to the Dell brick or a Corsair SF600.
 

Kmpkt

Innovation through Miniaturization
KMPKT
Feb 1, 2016
3,380
5,917
And yet, here is the weird thing. Even though this combo is less power efficient than other solutions, this is the one combo that has reduced the coil whine I experience from my GTX 1080 the most compared to the Dell brick or a Corsair SF600.

Things like this make me wonder if there is some unknown metric to do with the quality of power delivery regardless of wattage that may have more to do with coil whine than the rated wattage of the power unit being used. As an example, I'd be really curious to see someone with a coil whine prone setup make several sets of wires of different AWG (16, 18, 20, 22) to power the GPU and see if there is a difference.
 

Reldey

Master of Cramming
Feb 14, 2017
387
405
Things like this make me wonder if there is some unknown metric to do with the quality of power delivery regardless of wattage that may have more to do with coil whine than the rated wattage of the power unit being used. As an example, I'd be really curious to see someone with a coil whine prone setup make several sets of wires of different AWG (16, 18, 20, 22) to power the GPU and see if there is a difference.

Me too, maybe one day when I retire my GTX 1080 mini, I'll put it on a bench and go to town with different setups trying to figure out what can reduce it. It is one of the more annoying things I have ever dealt with in computing....