Help me design the perfect mini-ITX case?

[a5cent]

Introduction

I’m disappointed with the current selection of mini-ITX cases on the market. They always seem to lack something. Some are just far too large (repurposed ?ATX cases). Some ship with a built-in but poor PSU (power supply unit). Others don’t support large radiators for water-cooling, are a pain to build in, or don’t support large graphics cards.

None of the existing options met all of my requirements, so I decided to design and build my own. What I’m presenting here is still in its early stages; nothing is yet set in stone, so any and all feedback is welcome. Help determine how the design should evolve! Help make this case the best it can be!

Eventually, provided enough people like the result of this collaborative effort, I’d like to start a crowd funding campaign. The idea is to build enough units so each can be bought at an affordable price. However, now is neither the time nor is WPC the place for such discussions. This thread is only about your opinions/feedback. I will eventually move this discussion over to a more PC enthusiast focused site, but WPC is where I’m most at home on the internet, which is why I wanted to present it here first.

Who's it for?

• The water-cooling enthusiast
• The overclocker
• The LAN party gamer
• Anyone that wants a high-performance desktop PC with a small footprint and appreciates minimalistic but elegant design.

Goals

• As small as possible, but not at the expense of air-flow, cooling performance, or silent operation.
• As small as possible, without sacrificing the ability to fit large GPUs and an ATX12V PSU up to 180mm in length.
• Support dual 140mm radiators.
• Easier to build in than any other mini-ITX case.
• Support both positive and negative air pressure configurations.
• Good cable management options.

 

[a5cent]

Front
All images portray the case approximately 0.5" taller and 1" deeper than I intend it to be when completed. Some things are incomplete or missing entirely, e.g. in the image above, you'll notice that there is only a hole where the front I/O panel should be.


Side
A view through the side panel onto the motherboard.


Rear (without top panel)
The case will fit almost any all-in-one or dual 140mm radiator currently on the market, up to 36mm thick (here depicted with a Magicool 280 Slim radiator). Dual 120mm radiators are also fine. However, for anyone wanting to go crazy, the top panel can be removed as shown above, after which radiators of any thickness and length (up to 154mm wide) can be mounted. Not only does this allow us to mount huge radiators with integrated reservoirs and pumps, but it also removes any hindrances to airflow exiting the case, while exposing the radiator entirely to the outside air, allowing for best possible cooling performance.


Top


Frame (without components, hull or panels)
The hardened motherboard standoffs are not flimsily screwed into the motherboard tray. Instead, they are pressed into a precision drilled hole with a two ton punch/anvil, causing parts of the metal tray to cold-flow around the standoffs, securely holding them in place. This is very robust, but more importantly, it entirely removes the need for threads in the motherboard tray which are easily stripped. The same approach is used to provide threads where the PCIe brackets are fastened to the frame.

The lower round grommet is just a place holder. It will end up being the same shape but approximately half as long as the grommet above it, and extend to the bottom of the tray.

I have yet to include drive bays/mounts of any kind (HDD, SSD, ODD). How many drives of what type (2.5" or 3.5", DVD) do you think a case like this should accommodate? Would you want a spot to mount a DVD drive (see the EVGA hadron for how this might work)? Would you want more than two 3.5" mounting points? Would you want 3.5" mounting points at all?


Frame Top (without fans)


Frame Top (with 2x 140mm fans)
Using only the top mounted fans, cool air is drawn into the case through the ventilated side panels (the entire right side and the bottom left side). About 1/3 of the total air intake is drawn over the motherboard before it is exhausted out the top.


Back Right (without PSU)
Not shown: the foam rubber strips on the floor and tray hems, against which the PSU rests.


Back Right (with PSU)
Shown with a 180mm PSU.
Not shown: the latch that securely holds the back of the PSU in place.

I'm looking for a better way to suspend the tray (see the cross beam?). I'd prefer something that is simpler and that isn't visible through the side window. Any ideas?


Back left (with motherboard)
This is how a 180mm long ATXV12 PSU and a large GPU is able to fit in a case of this size! The trick is achieved by moving the expansion card (most likely a GPU) off the motherboard and into the cavity below it. The GPU is inserted into the lower/white PCIe socket. The lower/white PCIe socket is connected to the red PCIe socket on the motherboard using a high quality, impedance matched (85ohm) and EMI shielded PCIe extender cable.

This allows the motherboard to be moved towards the centre of the case, providing enough room to mount the PSU behind it.




Frame (with components but without hull and panels)
The extension card (most likely a GPU) is represented only by the bracket and the PCB (here at a length of 12.3" [312cm]).

Something to think about: a water-cooled GPU requires but a single PCIe slot. The current design has three PCIe slots, because some high-end air-cooled GPUs (see this) require that amount of space. Is this really necessary for a case intended primarily for water-cooling? Wouldn't two PCIe slots and a somewhat shorter case be preferable? Even with two PCIe slots, there is still enough space below a water-cooled GPU to mount additional 2.5" drives (small HDDs or SSDs). What would you do/want?

 

[a5cent]

Preliminary specs

This will be updated as the design evolves based on your feedback.

[table="width: 900"]

[tr]
[td]
Material[/td]
[td]
100% Aluminum
Outer hull: Manufactured from a single strip of aluminium. 2.5 mm thick.
Inner frame: 1.5 mm thick
[/td]
[/tr]

[tr]
[td]
Motherboard
[/td]
[td]
DTX, mini-ITX
[/td]
[/tr]

[tr]
[td]
Drive Bays
[/td]
[td]
External: TBD
Internal: TBD
[/td]
[/tr]

[tr]
[td]
Fan Mounts
[/td]
[td]
2x 140 mm or 2x 120 mm (top, exhaust)
1x 180 mm (front, intake optional, achieves positive pressure inside the case)
[/td]
[/tr]

[tr]
[td]
PCIe Expansion Slots
[/td]
[td]
3 (thinking a water-cooling focused case probably only needs two)
[/td]
[/tr]

[tr]
[td]
Front I/O
[/td]
[td]
2x USB 3.0
1x Audio
1x MIC
[/td]
[/tr]

[tr]
[td]
Power Supply
[/td]
[td]
Standard ATX12V
Up to 180 mm depth
[/td]
[/tr]

[tr]
[td]
PCIe Card Length Limit
[/td]
[td]
Up to 12.3“ [312 mm]
[/td]
[/tr]

[tr]
[td]
PCIe Card Width Limit
[/td]
[td]
Up to 2.5“ [64 mm] 3-PCIe Slots
[/td]
[/tr]

[tr]
[td]
CPU Cooler Hight Limit
[/td]
[td]
Up to 3.1" [80 mm]
[/td]
[/tr]


[tr]
[td]
Radiator
[/td]
[td]
Up to 2x 140 mm (also supports 2x 120 radiators or AIO products)

With top panel:
• Up to 323 x 154 x 35 mm

Without top panel:
• Any thickness
• Any length
• Up to 154 mm width
[/td]
[/tr]

[tr]
[td]
Dimensions
[/td]
[td]
TBD
Width: < 7" [180 mm]
Height: ~12.9" [~ 330 mm]
Depth: ~ 13.7" [~350 mm]
[/td]
[/tr]

[/table]

 

[Akash Patel]

So, I decided to bump this once. Not getting many views in this forum, which isn't surprising, considering it's WPC ;-)

buddy i think you should take some design from the already available mini itx case like corsair 250D,Cooler Master Elite 130.
personally i like the design of corsair 250D.
Your design looks good too but i found one flaw that if we attach a radiators like corsair h100i the back plate of that cooler will be tightly in contact with the psu might be wrong too as in the image it look like that way but in reality it wont be like that way

 

[gedzum]

This is looking really good. I like the concept. It's not really a form factor I've really thought about, so I'm not too sure what to suggest. The Corsair Air 540 is probably the closest thing to what I would consider like this but that is an ATX cube case. I like that you put the PSU on the other side of the motherboard tray. That should definitely allow for a cleaner look and easier cable management. I'm looking forward to seeing how this concept develops. Hope it works out for you. For sure I'd like to see a finished prototype of this.

 

[a5cent]

I found one flaw that if we attach a radiators like corsair h100i the back plate of that cooler will be tightly in contact with the psu might be wrong too as in the image it look like that way but in reality it wont be like that way

Hey Skyrocker

Thanks for your feedback! I'm sorry for not getting back to you earlier (been busy).

I'm not 100% sure I understand what you are saying. I think you are saying that the limited space between the top of the PSU and the bottom of the fans would too severely restrict air flow (at least in the area above the PSU), essentially starving the fans for air. The ninth image, 'Back Right (with PSU)' is where this is best seen. Is that correct?

Looking at the right side panel, you'll notice that it is almost entirely ventilated. You can't tell just from the images, but the ventilated area reaches right up to the horizontal plane above which the fans are mounted. The vertical distance from the top of the PSU to the bottom of the fans is roughly 1.4" [exactly 35 mm]. This is the ventilated area through which enough air must flow to satisfy the needs of ? of one top/rear 140mm fan.

Basically, the air passing through the right side of the radiator doesn't come from inside the case, but is in fact cool air that is drawn into the case directly from the outside through the right side panel. Only on the left side is air really being pulled through the entire case (and over the motherboard).

What do you think? Do you think that would be enough, or would that worry you (honest opinion please)?

I think that amount of ventilation area should satisfy the needs of half a fan. However, I do still see room for improvement, so I'm working to lower the PSU another half inch, increasing the ventilation area through which the top/rear fan can draw air by that same amount. Another problem I see is that someone might decide to shove cables into the space above the PSU, which truly would impair air flow. I'll need to find a way to prevent that.

On a side note, fan less PSUs are almost 100% permeable to air. Such a PSU would allow the top fan to pull air through the entire right side panel AND it would cool the PSU while doing so.

 

[QwarkDreams]

Nice work! It reminds me of the Aerocool DS but with the hardware placed differently (plus enough room for a 240 rad).

What confuses me a bit is the white PCI-e slot under the PSU. What's it for? Doesn't look like it is connected to the MoBo.

 

[a5cent]

buddy i think you should take some design from the already available mini itx case like corsair 250D,Cooler Master Elite 130.
personally i like the design of corsair 250D.

Anything in particular you think I should be aware of?

I don't think either of those are bad cases, but they just don't satisfy me. Foremost, I'd consider both of them too big for what they achieve. In particular, I'd prefer something with a much smaller footprint, which occupies less space on your desk (I actually hope to go even smaller than currently shown). Here is a size comparison (I also threw in the Air 540 because gedzum mentioned it):



Notice how the Corsair Obsidian 250D is barely shorter than this case, but almost twice as wide? Measured in volume, this case is almost the same size as the very small Elite 130, but the Elite 130 can mount only a single 120mm radiator, whereas this case can mount a 280mm radiator, which is even larger than what fits into the Obsidian 250D!

It's not easy to convey what I'm trying to achieve here. Maybe you folks can help me make it clearer?

I'm attempting to design a case that is as small as the smallest ITX cases out there, while still fitting components that typically require much larger cases. None of this should come at the cost of cooling performance. IMHO no compromises is a fitting slogan. In fact, outstanding water cooling performance is one of this cases main goals, particularly for those intending to water cool both the CPU and a high-end GPU. For such a setup, most will recommend a 360mm or 280mm radiator. For a 360mm radiator you really need a full sized ATX case however, which is why I went with the 280mm. If you remove the top panel, you can even mount 280mm radiators of any thickness, like the Alphacool NexXxOs Monsta (not that I personally would want that, but it does allow you to go crazy if you choose to).

Compare the specs and contrast that to the size and tell me what you think.

 

[a5cent]

Nice work! It reminds me of the Aerocool DS but with the hardware placed differently (plus enough room for a 240 rad).

What confuses me a bit is the white PCI-e slot under the PSU. What's it for? Doesn't look like it is connected to the MoBo.

Thanks! Actually, it fits a 280mm rad! That provides almost the same surface area as a 360mm rad and thus provides similar performance. Perfect for a water cooled CPU/GPU setup. :smile:

That PCIe socket is really the whole trick to this design. That is where the GPU is inserted. I tried to explain it, but maybe I failed? Can you take a look at the tenth image 'Back left (with motherboard)' and read the text below it? If that isn't clear maybe you could tell me where I screwed up so I can provide a better explanation? I would really appreciate that!

Note: what isn't shown in the rendering is the PCIe extender cable that connects that PCIe socket to the motherboard.

 

[QwarkDreams]

Thanks! Actually, it fits a 280mm rad! That provides almost the same surface area as a 360mm rad and thus provides similar performance. Perfect for a water cooled CPU/GPU setup. :smile:

That PCIe socket is really the whole trick to this design. That is where the GPU is inserted. I tried to explain it, but maybe I failed? Can you take a look at the tenth image 'Back left (with motherboard)' and read the text below it? If that isn't clear maybe you could tell me where I screwed up so I can provide a better explanation? I would really appreciate that!

Note: what isn't shown in the rendering is the PCIe extender cable that connects that PCIe socket to the motherboard.

Ah, now I get it. Must've missed this paragraph. What will the cable cost?

 

[Akash Patel]

Hey Skyrocker

Thanks for your feedback! I'm sorry for not getting back to you earlier (been busy).

I'm not 100% sure I understand what you are saying. I think you are saying that the limited space between the top of the PSU and the bottom of the fans would too severely restrict air flow (at least in the area above the PSU), essentially starving the fans for air. The ninth image, 'Back Right (with PSU)' is where this is best seen. Is that correct?

Looking at the right side panel, you'll notice that it is almost entirely ventilated. You can't tell just from the images, but the ventilated area reaches right up to the horizontal plane above which the fans are mounted. The vertical distance from the top of the PSU to the bottom of the fans is roughly 1.4" [exactly 35 mm]. This is the ventilated area through which enough air must flow to satisfy the needs of ? of one top/rear 140mm fan.

Basically, the air passing through the right side of the radiator doesn't come from inside the case, but is in fact cool air that is drawn into the case directly from the outside through the right side panel. Only on the left side is air really being pulled through the entire case (and over the motherboard).

What do you think? Do you think that would be enough, or would that worry you (honest opinion please)?

I think that amount of ventilation area should satisfy the needs of half a fan. However, I do still see room for improvement, so I'm working to lower the PSU another half inch, increasing the ventilation area through which the top/rear fan can draw air by that same amount. Another problem I see is that someone might decide to shove cables into the space above the PSU, which truly would impair air flow. I'll need to find a way to prevent that.

On a side note, fan less PSUs are almost 100% permeable to air. Such a PSU would allow the top fan to pull air through the entire right side panel AND it would cool the PSU while doing so.

no i didn't meant that wait i will get a picture of your design and tell you more precisely




hope this might help you

 

[Muessig]

I really like the look of this case. I'd hope the PVC window on the left hand side would be optional, because I prefer my cases not to have windows. Maybe I'm weird.

If I were to get this case I'd like the ability to load DVD's or CD's or Blu-ray's, so a drive bay would be essential. Some space for 2.5 and 3.5" bays would be needed too, but for me I'd only need space for max. 2 of each type.

 

[a5cent]

no i didn't meant that wait i will get a picture of your design and tell you more precisely


View attachment 69217

hope this might help you

Okay, now I understand. This is the clearance I've got right now:

8.5 mm Motherboard standoffs
1.5 mm Motherboard tray thickness
6.0 mm Hems against which the PSU rests

15.5 Total clearance

That is enough for the CPU back plates I'm aware of, but I don't own a Corsair H110i, so I can't really say. Just by looking at the images on the web I'd say that should work. However, I wasn't able to find any information detailing CPU back plate clearance requirements for the H110i, so I can't be sure. Do you know if 15.5 mm would be enough, or do you own such a radiator so you could check?

Also, what are your thoughts on the other issue we discussed (see post #8)?

 

[a5cent]

Ah, now I get it. Must've missed this paragraph. What will the cable cost?

That is a very good question. Unfortunately, I don't yet have a definitive answer, and probably won't for a quite some time yet.

That is because it all comes down to (a) production volume, (b) production volume, (c) production volume, and oh yeah, also (d) quality. :smile:

To get a custom designed PCIe extender cable built, one needs to order at least a few hundred pieces. The minimum order number varies from one company to the next, but on average it's around 500. The most affordable custom designed PCIe extender cables at that volume cost are around $8. However, in terms of quality I find these completely unacceptable. I won't compromise on quality when it comes to the PCIe extender cable, meaning it will be more expensive than $8. I hope it will be less than $15, but it could be much less if production volume is far above 500.

Hard to say without specific numbers, but I hope that gives you an idea.

 

[jhoff80]

Honestly, you'd be better off in the Hardforum.com Small Form Factor section for this kind of discussion.

For example, the Ncase M1 design done there (and commercialized in small numbers) is very similar to what you're already building. It only supports dual 120mm radiators though. At the very least, you might want to look into any design issues or successes that they ended up having.

Personally though, not perfect for me at all. I just moved my mini-ITX gaming build to a Silverstone ML07 because that had the slim home theater component style design I was looking for.

 

[a5cent]

Personally though, not perfect for me at all. I just moved my mini-ITX gaming build to a Silverstone ML07 because that had the slim home theater component style design I was looking for.

Hey jhoff80

Yup, if you're in the market for a home theatre PC, then a high-end desktop case isn't what you are looking for. But if you ever want a high-end mini ITX case, be sure to check back here ;-)

For example, the ncase M1 design done there (and commercialized in small numbers) is very similar to what you're already building. It only supports dual 120mm radiators though. At the very least, you might want to look into any design issues or successes that they ended up having.

I can see how one might think the M1 and what I'm trying to build are similar. The ncase team and I both want a case that supports a CPU/GPU water cooling loop, we care about size, and we care about build quality. However, other than that I think we have very different approaches.

The ncase team set out to build the smallest possible high-end mini-ITX case and subordinated all else to that goal. In contrast, I started out with the requirements to fit a 180mm ATX PSU, a very large GPU, and a commitment to uncompromised water cooling performance. Only after drawing that line in the sand did I consider how to fit that into the smallest possible volume. As a result, what I'm building here will be as small as the smallest mini-ITX cases from the established manufacturers (while offering room for more powerful components), but it won't be quite as small as the M1.

Anyway, for my personal preferences, the M1 leans to heavily to one extreme. Size matters, but IMHO some things should outweigh size considerations:

• particularly for those with high-end graphics cards, a 240mm radiator isn't sufficient. Even under perfect air flow conditions, that would require the pump and fans to work harder than is optimal.
• in the M1, the fans pulling air in through the radiator blow it right up against the motherboard. That alone severely obstructs air flow, but with a CPU/GPU water cooling loop installed, the interior of the M1 is so cramped with tubing and cabling, that air has no unobstructed path through which to flow out of the case. That drastically limits the amount of air those two fans can pull in through the radiator, further inhibiting cooling performance, and requiring the pump and fans to work even harder.
• harder working pumps and fans also means louder pumps and fans, and I'd prefer a high-performance PC that is silent.

Don't get me wrong. I think the ncase team made what is the closest anyone has ever gotten to a perfect mini-ITX case. If I had seen the M1 back then, I probably would have bought one, despite it not being exactly what I want. I probably just wouldn't have used it for my main PC.

Anyway, I'm glad the ncase team made their case (pun intended). I consider its existence further proof that case manufacturers aren't building what the enthusiast community wants, and that we are justified in trying to design and build these cases ourselves.

Honestly, you'd be better off in the Hardforum.com Small Form Factor section for this kind of discussion.

Yeah, when I'm further along, this thread will move over there. It's just that I'm most at home here at WPC so I wanted to launch it here first ;-)

 

[Akash Patel]

Okay, now I understand. This is the clearance I've got right now:

8.5 mm Motherboard standoffs
1.5 mm Motherboard tray thickness
6.0 mm Hems against which the PSU rests

15.5 Total clearance

That is enough for the CPU back plates I'm aware of, but I don't own a Corsair H110i, so I can't really say. Just by looking at the images on the web I'd say that should work. However, I wasn't able to find any information detailing CPU back plate clearance requirements for the H110i, so I can't be sure. Do you know if 15.5 mm would be enough, or do you own such a radiator so you could check?

Also, what are your thoughts on the other issue we discussed (see post #8)?

H100i will fit definetly as the back plate is hardly 1cm-1.2 cm but not sure about h105 and h110 as they are new so none of my friend have them.
Mostly they will fit more tightly to the psu but i guess it wont be a issue but if they are slightly higher then they might create problem.

make sure you add a front fan like available in corsair 250D and try adding a dvd drive bay.

i dont remember the bracket which allow us to install ssd on one side and hdd on other side if you get i what i mean try using them

 

[a5cent]

I really like the look of this case. I'd hope the PVC window on the left hand side would be optional, because I prefer my cases not to have windows. Maybe I'm weird.

If I were to get this case I'd like the ability to load DVD's or CD's or Blu-ray's, so a drive bay would be essential. Some space for 2.5 and 3.5" bays would be needed too, but for me I'd only need space for max. 2 of each type.

Glad that you like the case! Sorry for not getting back to you sooner. I've been very busy at home, and while moderating is quick and simple, this requires more time. ;-)

The reason it has a side window is because it's expected that many people with this case would install a water cooling loop, which is often an aesthetically pleasing sight:

http://www.youtube.com/watch?v=jVPehMaHgM8

Such a setup deserves to be shown IMHO. Either way though, I see no reason why a case couldn't be provided without a side window. Just leave out a few steps and presto! :smile:

What I'm most unsure of are the mounting points for 3.5" drives. The best place to put them would be below the water cooled GPU, where there is more than enough space because a water cooled GPU is at most one PCIe slot thick. Unfortunately, those people with a water cooled GPU are also those who are least likely to use any 3.5" drives at all, as most will have fully transitioned to 2.5" SSDs. That leaves only the front of the case where they somewhat conflict with air flow and cooling considerations, which I won't accept. So, still thinking on that one.

Ideas are very welcome of course.

My personal opinion is that ODDs (optical disk drives) are legacy equipment, like floppy disks. Almost all software is downloaded over the internet these days, including operating systems, MS Office and even games. If you don't transfer you files through the cloud, there are always USB drives, which are faster, don't scratch, and have higher capacities than even DVDs. I personally have no use for an ODD drive, but I imagine a lot of people see that differently, so I do plan to provide a mounting point, although it will be of the slim, slot loading variety. I'm still thinking about placement and in which direction media should be ejected (left, right, top).

What do you think?

 

[gedzum]

I share your opinion regarding ODDs. I still personally have an internal DVD drive and have recently got an external blu-ray drive though. But in terms of an enthusiast, small form-factor case, aesthetics and space may be priority and in that case, the need for an ODD may not be necessary. If it may be required, then external drives can be an option. A slim, slot loading drive can be a comprimise though, if an ODD is desired.

 

[a5cent]

I share your opinion regarding ODDs. I still personally have an internal DVD drive and have recently got an external blu-ray drive though. But in terms of an enthusiast, small form-factor case, aesthetics and space may be priority and in that case, the need for an ODD may not be necessary. If it may be required, then external drives can be an option. A slim, slot loading drive can be a comprimise though, if an ODD is desired.

Exactly. I expect I will be able to get a slot loading drive in there without sacrificing aesthetics or size though. If I have to sacrifice either, then I'd prefer to drop the ODD drive. Stay tuned to find out! ;-)

What is bugging me most right now are the mounting points for 3.5" drives. 3.5" HDDs generate a lot of heat and require a lot of space, which I'm quite unhappy about, particularly since I'm on the verge of declaring 3.5" drives legacy equipment too.

2.5" HDDs in 1.5TB and 2TB capacities have been available for almost two years now. They are readily available everywhere, they are just as fast as their larger brothers, and they require less power (less mass to spin), meaning they dump less heat into the case. The only thing 3.5" drives have going for them are the larger 3TB and 4TB capacities, but I think those of us who require that much storage will usually have a NAS around somewhere.

Anyway, I'd like to shrink the case down even further, but supporting 3.5" drives would prevent that. Add to that the mentioned heat considerations and I'm leaning towards not providing any 3.5" mounting points at all (it should provide enough room for at least six 2.5" HDDs and SSDs). I'm just worried this could be too forward looking.

Thoughts? Opinions?