Mini-Splash, about a Gallon water cooled SFF gaming PC

[Goatee]

I did some tinkering over the weekend, I will have some screenshots and stuff up later today / tomorrow on the actual build.

I am however encountering an issue and I hope someone can maybe help me think of a few options I may have missed. Thanks to @aquelito I have managed to trouble shoot the problem, now I hope to come up with a slightly less drastic solution!

The background;

I use a dell 330w laptop PSU, which runs from the barrel connector (powering the board @ 19V), and a HDPLEX DC-ATX (again at 19V). THe HDPLEX powers the following:

GPU - Katana 1070 - (single 8 pin)
Powered x4 PCIE riser - (Berg connector from a sata power connector)
The board is powering everything else.

To switch the HDPLEX on when the motherboard powers up I am using a mosfet from the 12V fan header. This mosfet, when powered bridges the neutral and PS_ON on the HDPLEX turning it on (like using a paper clip).


The issue:

The 12V line from the GPU (both when powered by the 8 pin connector or when using the powered riser) is flowing back through the PCIEx4 cable and is powering the board with 12V even when the board is turned off. This means that the fans, pump and HDPLEX all remain turned on even when the board is turned off.

To make sure this was the issue (not some random board setting) I created the following adaptor to isolate the 12v supply from the motherboard PCIEx4 connector. This plugs in and makes sure no 12V will flow from the board to the GPU (or in reverse). (Its too tall to be a permanent solution, and requires daisy chaining two ribbon cables)

When using the adaptor I no longer see the issue.

Now the solution!

I could just file / grind away the 5 x 12V fingers from the powered riser cable I am using, repeating the process I did on the 90 degree riser. This is a bit permanent, so I tried covering the fingers with tape, but this just causes the tape to come away when inserted into the motherboard.

I could try acrylic nail polish (perhaps a nice red shade) which should withstand a few inserts and would break the electrical connection and should be removable in future, but I'm not sure if this would work.

Anyone got any other clever ideas?

 

[Canities]

Now the solution!
I could just file / grind away the 5 x 12V fingers from the powered riser cable I am using, repeating the process I did on the 90 degree riser. This is a bit permanent, so I tried covering the fingers with tape, but this just causes the tape to come away when inserted into the motherboard.
I could try acrylic nail polish (perhaps a nice red shade) which should withstand a few inserts and would break the electrical connection and should be removable in future, but I'm not sure if this would work.
Anyone got any other clever ideas?

Just a quick idea, couldn't you cut the 5 power wires on the riser cable and add some diodes to them?
If done properly, the current would only flow in one direction (from the board to the card).

 

[Elerek]

Just a quick idea, couldn't you cut the 5 power wires on the riser cable and add some diodes to them?
If done properly, the current would only flow in one direction (from the board to the card).

Not sure if diodes would be a good idea, they add a significant amount of resistance and could potentially overheat with 75 watts being pulled through them. Mosfets could work though, just use them like the power on mosfet.
But if the card works without pcie power (apparently it is) then he could just cut them and leave them cut.

 

[Goatee]

Im going to try some Kapton tape, amazon are delivering tomorrow.

 

[Goatee]

Update time number 11 (.... I think!)

Kapton tape worked a treat.

I really liked the multiple temperature monitoring of the non-contact thermometer, and I wanted to play around with fan and pump settings in windows, so I decided to put an aquaero in as well. I have an an Aquaero 5 LT that I have used in a couple of builds over the past few years and I love the level of control it offers.

However, it adds lots of cables. I think I added at least 2 more after this picture was taken.

I made a side mounting bracket for the Aquaero, utilising the "white space" I identified previously.

After some cable tiding, heat shrinking, zip ties, and other magic, i ended up pretty neat. Im really pleased with how clean it looks.

I also found some more space, can you guess what this is for.....

Yep, another fan! I have an Aquaero to power it from after all. This fan will exhaust and is a 60mm Noctua. I had to do some real cable bending to get in in there, but it works just fine.

I have the following left to do:

* Shorten and make the HDPLEX power connections low profile so I can fit the back panel.
* Add connector block to fix the back panel
* Beat the **** out of the plastic panel supplier who still hasn't got me my window panel in the correct size, I only ordered it at the beginning of December and they have sent it twice in the wrong size!
* Add a power button (I found a donor case in my cupboard)
* Add mounting should the window ever arrive
* Fix a couple of niggles
* Prep and finish the surfaces of the panels.
* Tweak and finalise Fan and Pump settings then do final bench marks
* Take some nice pictures outdoors

Not much left to do. Its going well

 

[Goatee]

Thanks for all the likes, its really nice to know others are interested in what I'm doing. So update 12 inbound!!

I needed to replace the mosfet that switches the HDPLEX on when the board powers up. I one I had been using failed (most likely damaged when I was trying to figure out the 12V flow back down the PCIE cable). So I ordered a new one from RS and got soldering, shortening cables and cutting up connectors. The mosfet is this one if anyone is interested in the future: MOSFET N-Channel 55V 47A TO220AB

Thanks @aquelito for all the help.

Next was to fit a power button to the case. I was fed up of sticking a screwdriver in to short the motherboard to start it up each time. A step drill and power button from my bits box and it looks really nice.

I did notice when I tightened everything up that it can make contact with the radiator. I will need to isolate it with heatshrink as tts pretty tight (not that I have said that much in this build!!)

Next I moved onto start tidying up the cables at the back of the build. The had just been left flapping in the wind the entire time and I wanted to try enclosing the case to see thermals. so some shortening and

I have run out of zip ties, so its not quite complete, but I can now get a back panel on.

Stuff left to do:
* Shorten and make the HDPLEX power connections low profile so I can fit the back panel.
* Add connector block to fix the back panel
* Add a power button (I found a donor case in my cupboard)
* Beat the **** out of the plastic panel supplier who still hasn't got me my window panel in the correct size, I only ordered it at the beginning of December and they have sent it twice in the wrong size! - Its now back in "production".
* Add mounting should the window ever arrive
* Fix a couple of niggles
* Prep and finish the surfaces of the panels.
* Tweak and finalise Fan and Pump settings then do final bench marks
* Isolate the power switch terminals to stop accidental contact.
* Take some nice pictures outdoors

 

[Goatee]

Mini update:

Window arrived (this is the third time it’s been supplied) and it’s still too small.

Pretty annoyed! So I took my vandal switch out and cut it in half to see how it works.

I will need to mod that to fit it back in but much smaller!

 

[Goatee]

Update 13: Unlucky for some.

As previously mentioned I decided to cut my vandal switch in half as it was marginally too long and I want to see how it works. It was going to be slightly difficult to undo.

As you can see its a fairly basic operation, pressing the button at the front pushes an isolated piece of metal that makes contact with the two connections, triggering the motherboard.

Here is my solution.

* Bottom left - Is the cut down (to about half size) vandal body

* Bottom middle - Is the original spring, I ended up cutting this down slightly given the reduction is overall length.

* Bottom right - Part of a water cooling compression fitting I found it my bits box. It has exactly the same thread and size as the outside diameter of the vandal thread.

* Top left - This is the smaller replacement isolated "trigger". Its made of a rubber HDD idolater, nylon standoff and a screw. The original button is reused.

* Top Right - A pair of terminals (metal standoff's) that have a small heat shrink sheath over the top. These are screwed into a piece of plastic the same diameter as the vandal body, they stick out slightly the other side giving to contact for the replacement trigger (screw) to to make.

Here is my highly technical diagram. Press the button and the screw makes the connection. Let go and the spring resets the switch breaking the connection.

And fitted:

In hindsight I could have used smaller stand-offs or even just some screws passing through the plastic. This could arrangement could then achieve a sub 15mm total depth for a vandal switch, but because I have 25mm to play with I just grabbed the nearest stand-offs I had, rather than worring about it. I have become lazy with a whole 10mm to play with. A complete luxury compared to the rest of the build.

 

[Goatee]

I am really pleased to have had my build be nominated, along with some other great builds for the January Bit-Tech modding update competition. I'm not keen on linking between sites, but if you are interested in voting for me and a Bit-Tech member, I'm sure you can find it.

Update 14

My updates have been slower recently, we have had a couple of issues with our heating in the house, some heavy snow and a bit of the illnesses that are always around this time of year. So other things took priority.

I have finally got the back panel on the case

Its currently in place using the power of friction, but will eventually be screwed in like the other panels. Fits like a glove!

Some money shots of the front, the simple, industrial look with exposed screws fits really nicely with the power switch I think.

In case you cant tell, I like carter root beer! (other root beers are available)

As a reminder here is the nice tidy cable work:

To do some stress testing (more to come on this in future posts) I stuck the undersized smoked panel in, again I really like the simple look.

To keep the industrial look going, I think I might just lightly sand the aluminium and not paint it. I'm weighing up options though, so if you have any clever ideas then shout!

 

[Aux]

yeah, I see you on bittech, good luck

 

[wolrah]

Great work! Thanks for posting. You have given me some ideas for my build.