Production S700: Salvo Studios <23L ATX Steel Watercooled Unibody Chassis

grsychckn

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In terms of surface area I think a 360mm radiator is slightly ahead of a 280 (all else being equal of course, in reality fin density and arrangement really comes into play).

As for the revised arrangement compared to the S700 prototype, I didn't really like it at first but I think it's starting to grow on me. My personal preference for this would be to have a 360mm radiator at the front rather than a 280mm. I think the narrower size should leave a bit extra room on the front of the case, potentially allowing a front IO panel? I know a lot of SFF cases eschews any front IO at all in the name of making the front panel clean and aesthetically uncluttered, but I really appreciate the utility of having easily accessible USB ports (even more relevant in a slightly bigger case like this, shifting a heavy watercooled rig around just so I can reach the ports on the back is a bit tedious).

I have a few suggestions/criticism of the latest batch of renders, mainly to do with the top panel, right now the whole of the top panel is a flat blank sheet. I don't think the rear of the case has enough clearance for an exhaust fan like conventional tower cases, so without anywhere for the heat to go, I think the motherboard VRMs will cook themselves slowly. Some perforations will be really helpful here I think (perhaps a bracket to fit a slim 120mm fan sucking air in from the side panel and blowing it straight towards the CPU socket? Or maybe the whole motherboard could be moved vertically downward enough for a couple of 80 or 92mm fans to fit at the top, extracting hot air and blow it out of the top panel (it seems like there's some wiggle room there since the motherboard is a ways away from the bottom floor of the case)

There's a decent amount of empty space directly above where the graphics card is mounted right now, is there enough room for another single-slot PCIe mount? Could potentially be useful for a high speed NIC card or something like that (or a sound card or capture card or something like that)
I had just begun putting holes in that version of the S700 and hadn't gotten around to placing things like other fan mounts on it. Above the motherboard, there is room to place 3 x 80mm fans and that is what I was planning on doing before my latest change to the design. I'm still not sure which one I'm going to go with ultimately, but I'll need to sell the S402 units in order to generate the development cash to make the S700 whichever one I decide to make.

I'm going to make some early renders of the newer design I've not show yet and post them here. I think it would be good to give an idea about what I'm trying to accomplish with this newer approach - even if it is not finished (including vent holes, mainboard/PSU/PCIe cutouts, button holes, etc.).

Edit: I also want to add that your idea of supporting an additional PCIe device is a good one, but adding the mounting hardware to do so might be expensive and it would limit the width of the two lower devices. I may see if there is another way I can cram support in for a third device, but I may want to locate it somewhere else. On the renders below, it could be made to fit between the reservoir and the PSU but the riser cable will be something else to consider.
 
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grsychckn

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Keep in mind, these are VERY early renders of a design I still have a lot of paying around with left to do. The only vent holes are the ones on the PSU, but rest assured, there will be vents on each of the radiators as well as across the rear so the air will have a place to escape. I think I won't add too many vent holes outside of the radiators though because I want positive pressure inside the case to help avoid as much dust collection as possible.



The space between the reservoir and the PSU would be where disks, etc. would be fit.
 

Vacceo

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Top radiator, not a bad choice at all and quite efficient for airflow. It also reduces the wasted space on the upper part you talked about before. It´s an elegant option and pre-heated air from the front cannot be THAT bad when 90% mainstream towers have a radiator disposition like that (Think of Fractal Design or Phanteks, to name a couple mainstream manufacturers).

Regarding VRM´s cooking themselves, I honestly think that if this is going to be a water-centric case that can use a full ATX, you might as well travel the extra mille and use a monoblock for the motherboard (monoblocks are far more common for ATX-sized than for smaller formats).

With this draft, what would be the aproximate lenght and thickness for radiators and fans in each location?
 
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duynguyenle

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Top radiator, not a bad choice at all and quite efficient for airflow. It also reduces the wasted space on the upper part you talked about before. It´s an elegant option and pre-heated air from the front cannot be THAT bad when 90% mainstream towers have a radiator disposition like that (Think of Fractal Design or Phanteks, to name a couple mainstream manufacturers).

Regarding VRM´s cooking themselves, I honestly think that if this is going to be a water-centric case that can use a full ATX, you might as well travel the extra mille and use a monoblock for the motherboard (monoblocks are far more common for ATX-sized than for smaller formats).

With this draft, what would be the aproximate lenght and thickness for radiators and fans in each location?

That's all well and good, but severely limits your component selection. How many motherboards on the market actually has monoblock made for them? As far as I'm aware, there are only two OEMs on the market for monoblocks, EK and Bitspower. And their monoblock selection is rather limited, to say the least. If you've got a high-end MSI X570 motherboard, what monoblock are you gonna get? What about TR4, how many TR4 monoblocks are on the market? I really think you're vastly over-estimating how common monoblocks are (even though you are quite right, they're *technically* more common that ITX monoblocks)
 
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duynguyenle

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Keep in mind, these are VERY early renders of a design I still have a lot of paying around with left to do. The only vent holes are the ones on the PSU, but rest assured, there will be vents on each of the radiators as well as across the rear so the air will have a place to escape. I think I won't add too many vent holes outside of the radiators though because I want positive pressure inside the case to help avoid as much dust collection as possible.



The space between the reservoir and the PSU would be where disks, etc. would be fit.

I'm liking this latest iteration a lot, I think this is a better arrangement for the second radiator (plus it makes space for other useful things at the back).

Good point about the second PCI slot, I suppose that would constrain your graphics card height. Would be really useful if you could add this support, but I suppose it is not worth compromising GPU support for that.
 

grsychckn

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With this draft, what would be the aproximate lenght and thickness for radiators and fans in each location?
The current renders are using an EK 280mm model that is 45mm thick + 140x25mm fans. So the top radiator has just over 70mm of clearance for rad + fans right now. The front has even more with the mainboard model I'm using (9.7" wide). That's a very slim width for a mainboard so I would think the same clearance on the front should be expected for a mainboard coming in around 10-11" wide.

Good point about the second PCI slot, I suppose that would constrain your graphics card height. Would be really useful if you could add this support, but I suppose it is not worth compromising GPU support for that.
There is always the possibility of making an adapter that will allow another device (or two?) to fit between the reservoir/pump and the PSU. The only problem I see here is the number of riser cables needed and where the best place is to make a cutout so the cable can be "snaked" through the mainboard panel to the other side.
 

Vacceo

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Capacity to go thicker than the usual 30mm radiator is quite tricky as I was considering options when I red your post. EK has a 45mm CE series and those are the only options for 140mm fans-multiples. They´re generally on par or a bit worse compared to HWL GTS. However, the thicker HWL size would be GTX on 54mm total, but that would push the total size close to 80mm. Bitspower offers the exact same situation as Hardware Labs. Alphacool jumps from 30mm ST´s to 60mm UT, so even worse. XSPC goes from super slim (20mm) to in between (35mm) to thickers (56mm). From top of my head I cannot remember more manufacturers, but I´m sure the situation is not too different.

All in all I´d say that going for a standard 30mm thick radiator in dual 280 should be perfectly fine, as it provides good cooling for a GPU and CPU and even a nice headroom to overclock. That also allows a good silence for the system, as thicker rads require higher RPM´s to work well or push-pull, making size even worse.

Personally, I think I´d stay with a dual 280 GTS, the extra room may even help with airflow as things would be not so tight.

Also, the location of the upper rad seems to be an excelent choise for those who will use an AIO, which is a perfectly fine option too.
 
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grsychckn

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Capacity to go thicker than the usual 30mm radiator is quite tricky as I was considering options when I red your post. EK has a 45mm CE series and those are the only options for 140mm fans-multiples. They´re generally on par or a bit worse compared to HWL GTS. However, the thicker HWL size would be GTX on 54mm total, but that would push the total size close to 80mm. Bitspower offers the exact same situation as Hardware Labs. Alphacool jumps from 30mm ST´s to 60mm UT, so even worse. XSPC goes from super slim (20mm) to in between (35mm) to thickers (56mm). From top of my head I cannot remember more manufacturers, but I´m sure the situation is not too different.

All in all I´d say that going for a standard 30mm thick radiator in dual 280 should be perfectly fine, as it provides good cooling for a GPU and CPU and even a nice headroom to overclock. That also allows a good silence for the system, as thicker rads require higher RPM´s to work well or push-pull, making size even worse.

Personally, I think I´d stay with a dual 280 GTS, the extra room may even help with airflow as things would be not so tight.

Also, the location of the upper rad seems to be an excelent choise for those who will use an AIO, which is a perfectly fine option too.
If I only support up to 30mm radiators, that means the total thickness for the rad/fan will be just over 55mm which has the potential to greatly reduce the overall dimensions and thus the volume as well. I'm going to play around with that some today.
 

Vacceo

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I don´t expect many people to go for an SFF or even compact computer case if they´re going balls to the wall on the hardware. Titans are not that common, so SLI´s of those monsters are even less common and year after year, not that worth it. Those are the kind of sets that require a huge amount of radiator surface. For a GPU and a CPU, even if we´re talking behemoths like Titans, 3950X´s, Intel 10th´s and overclocking, two 280 are plenty and even in those cases, you can get temperatures far from thermal throttling. Sure, it will be hot, but I cannot see many users building a setup of that kind (perhaps a big youtuber).

For something like a 3900x and a 2080 super, that cooling is perfectly fine and you´d even have a good headroom for overclocking even at relatively high room temperatures. Plus, Noctuas can work real magic on radiators...
 

duynguyenle

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If I only support up to 30mm radiators, that means the total thickness for the rad/fan will be just over 55mm which has the potential to greatly reduce the overall dimensions and thus the volume as well. I'm going to play around with that some today.

I have a couple of HardwareLabs GTX rads I would like to re-use (they have phenomenal performance) but I understand if this makes the case unreasonably large. For 30mm class radiators, there are actually some decent options out there, I suspect it should be OK for a 360x30mm and 240 or 280x30mm combo to take care of most hardware that could reasonably fit in an ATX form factor.

I would like to see what you can come up with and what the tradeoff is in terms of volume between a version of the case that supports thick radiator (i.e. the current iteration) vs one that only supports up to 30mm thick rads
 

Vacceo

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I have a couple of HardwareLabs GTX rads I would like to re-use (they have phenomenal performance) but I understand if this makes the case unreasonably large. For 30mm class radiators, there are actually some decent options out there, I suspect it should be OK for a 360x30mm and 240 or 280x30mm combo to take care of most hardware that could reasonably fit in an ATX form factor.

I would like to see what you can come up with and what the tradeoff is in terms of volume between a version of the case that supports thick radiator (i.e. the current iteration) vs one that only supports up to 30mm thick rads
On paper, going from a GTS to a GTX means an increase of around 3,5cm taller and another 3,5 cm longer case. Does not sound like much on paper but once you have the package, it may not be as small.

Truth be told, I´d love that posibility myself too, but the size may get out of hand.
 

grsychckn

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So for the top radiator, if the supported depth for the radiator + fan goes from the current 70mm down to 55mm (30 for rad + 25 for fans), that claws back 1.67L of volume. The volume change per 1cm in the vertical dimension is 1.08L. For me, making the chassis thinner side-to-side is where I get huge amounts of savings in volume because the side is the largest surface area (doubling the top and front easily).

Basically, the things killing me now in terms of volume are the D5 pump and the ATX PSU. If I only had to support a DDC and SFX PSU, I'd save at least 1cm on the overall side-to-side dimension. This would result in a volume change per 1cm of 1.5L.

I've been looking at distribution plates but even if I can trim down the D5, the ATX PSU requires the same space. Basically, I like what I have but just wish it were a little tighter - especially with large volumes of unused space like the area between the PSU and the pump. I'm sure someone would use that space, but then I'm making a ton of adapter brackets and increasing the hardware support to a level that is going to require tons of test fitting for clearances. Basically, I recognize I still have a lot of work to do to maximize the space.

So this latest design is weighing in around 29L right now. That's a far cry from the 24L of the original design but now there is built-in support for ATX PSUs, D5 pump/reservoirs, thicker radiators, etc. I'm selfish and what I want is to have a chassis that will support my Supermicro H11DSi-NT board for a dual Rome system. Therefore, the minimum supported mainboard dimensions will be 12" x 13". If you go with a standard 12" x 9.6" ATX board, the front radiator/fan combo clearance is currently just over 130mm. So there is potential to have a lot of unused space unless you go with a deep radiator on the front when using a standard ATX board.
 
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Allhopeforhumanity

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So this latest design is weighing in around 29L right now. That's a far cry from the 24L of the original design but now there is built-in support for ATX PSUs, D5 pump/reservoirs, thicker radiators, etc. I'm selfish and what I want is to have a chassis that will support my Supermicro H11DSi-NT board for a dual Rome system. Therefore, the minimum supported mainboard dimensions will be 12" x 13". If you go with a standard 12" x 9.6" ATX board, the front radiator/fan combo clearance is currently just over 130mm. So there is potential to have a lot of unused space unless you go with a deep radiator on the front when using a standard ATX board.

Is the necessity for ATX PSUs due to the dual CPU board? If there isn't significant space savings by switching to SFX/SFX-L, I can also see where supporting this form faction makes sense. However, at 29L you're getting pretty hefty and the feature/volume creep to support such niche systems (SSEB/EATX with ATX PSUs) might end up turning people away from the chassis.

I could have sworn that I've seen smaller pump/res combos that may suit this form factor better. It might be worth exploring that space, or even res/separate pump housings to better accommodate the current unused space at the rear at smaller thicknesses.
 
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grsychckn

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Is the necessity for ATX PSUs due to the dual CPU board? If there isn't significant space savings by switching to SFX/SFX-L, I can also see where supporting this form faction makes sense. However, at 29L you're getting pretty hefty and the feature/volume creep to support such niche systems (SSEB/EATX with ATX PSUs) might end up turning people away from the chassis.

I could have sworn that I've seen smaller pump/res combos that may suit this form factor better. It might be worth exploring that space, or even res/separate pump housings to better accommodate the current unused space at the rear at smaller thicknesses.
Exactly. I've had this thought in the back of my head for sometime now. I feel that my current SF750 platinum is capable of providing enough power to my dual Naples system but I do need to be careful when I stress the entire system (which I don't do often). I'm using it now as a Hypervisor host for work VPN sessions - and some F@H stuff in the middle of the night (GPU only). At idle I'm around 160W and under CPU stress test it's like 550W (all measured at the wall). I feel that there is still enough power envelope to leave my WX9100 (Vega 64) in there because it's highly unlikely I'll be stressing the CPU and GPU at the same time. Regardless, that's a risk I'm willing to take.

So let me see if I can list the pros/cons here of using the more compact components.

D5 pump vs DDC pump
D5-Pros: 1. Higher flow rate, lower pressure. 2. Claims to make less noise. 3. Can still use DDC if you wish.
DDC-Pros: 1. Half the size of the D5. 2. Higher pressure means more components in the loop. 3. Many smaller reservoirs available.

Max Flow Rate: D5-1500lph, DDC-1000lph
Head Pressure: D5-3.9m, DDC-5.2m

Addressing the cons:
D5 - In the context of lowering the volume of the S700, there would have to be a limit on the choice for the reservoir. Perhaps a distro plate from another design could be fit or a rectangular one like the Phanteks Glacier.
DDC - Rubber mounts to lower the noise and perhaps even support some dual-pump configurations. Also, mounting the pump separate from the reservoir makes a difference in the noise on the DDC.

I think the pros/cons speak for themselves with regard to the PSU. I'd love to fit everything back into the volume of around 24L so I'm heavily leaning towards trimming down this version of the S700 to see what I can fit.

Ultimately, because the S700 in it's latest state requires watercooling for all components, I feel the question of DDC vs D5 has to be answered. ATX PSU support is not really a hill I'll die on so the PSU support will depend on the pump choice.

Lastly, I will say that my DDC in the S700 prototype I have is loud. I don't know how much of a difference there is between it and a D5, but it is also a cheaper unit (Barrow I believe).

Edit: One last thing to note is that if I do drop support from full ATX/D5 down to SFX/DDC, I'll save approximately 5L but the slim ODD drive will probably have to be removed. Unless rear panel access is acceptable.
 
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Vacceo

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I guess turning the internal panel to attach the motherboard into a distro plate (something along the lines of what Singularity Computers does) would be a serious hassle to keep the original measures (the space for the GPU and motherboard would be narrower), but it may be possible. I the case of reducing the PSU, there are 750W SFX´s (Corsair makes one, I think), so for power requirements, it should be plenty.

On the original post of a thicker radiator, I would go for it with a standard ATX; others may think of push-pull configurations. The area between the reservoir and PSU can be used for SSD´s, loop controllers and so on. Regarding the ODD drive, that could be located on the floor of the case, right under the radiator or completely removed (there is always USB)
 
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duynguyenle

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Regarding D5 vs DDC, there's a couple of other things to note: DDC pumps do need active cooling in order to ensure reliable operation and to prolong the life of the pump. This is due to the differences in design (D5 pumps have a metal body in direct contact with the working fluid which the pump electronics can sink their heat into, whereas for the DDC the PCB is not coupled to the fluid flow in any way, thus the conventional wisdom is DDC pumps should be used with a proper heatsink on the bottom of the unit (IIRC a passive finned aluminium heatsink is usually adequate)

As for the DDC noise, I should point out that DDC pump response curve is a little bit screwy, past about 60% or so the pump already reaches basically it speed ceiling, and it quite noisy. Between 30-40% PWM duty cycle is where a DDC is most tolerable (at least in my experience). Here's a chart from TPU's recent review of a DDC-containing Corsair reservoir unit (this behaviour is pretty typical of DDC units):



If you have a DDC unit to hand, I would be interested in whether you can keep the pump noise at a managable level within this PWM range (30-50%). If you already have one hooked up to your prototype build, I'd quite like to see the differences in temperature of your particular loop as well (perhaps with some flow measurements, if you happen to have a flow meter for testing). Although I do overall prefer the noise profile of D5 pumps (they're perceivable less 'whiny' than a DDC, I don't tend to run my D5 flat-out, as even the quieter D5 is quite noticable at full tilt.

For a loop with high restriction (multiple blocks/reservoirs, with some angled/90 degree fittings thrown in, the D5's advantage in absolute flow rate drops off pretty rapidly. I have attached a pressure/flow rate curve below for comparison, as you can see from the upper left region of the chart, at higher backpressure, a DDC can actually develop higher overall flow rate than a D5, visualised by the area of the curve where the Corsair X'D3 (DDC) is above the curve for the X'D5 (D5)



Obviously this is a relatively simplified view of things, in the real (and messy world) there are a lot more variables that affect pressure head and flow rate even for the same pump. This is back in the days where manufacturers actually put thought and engineering resources into pump block design. These days, it seems most manufacturers just focus on pretty rainbow lights because even a sub-optimal pump top design is usually 'good enough'. But I suppose that is a discussion for another day.

I guess all that long-winded prose is mainly for me to say I don't have a particular preference on either the D5 or DDC, both of them can develop 'good enough' flow rate for even loops with relatively high restriction and both of them can be made 'quiet enough' for daily use (though the D5 still has the edge in this case). DDC is definitely more compact. Due to the large diameter of the D5, it sorta sets a minimum size floor for most cylindrical reservoirs on the market. But having a quick look around at DDC pump/res combo units, I don't think they're that much smaller either (with the notable exception of the 'flat' units like the Phanteks R160/R220 or the obviously inspired Bykski TK180).

As for the PSU debate, for SFX (and by extension, SFX-L units) can get up to 800W at the moment, though Silverstone has already teased a 1000W SFX-L unit at Computex last year and Enhance has also teased a 1000W SFX unit so I don't think we're missing out too much on power compared to ATX PSUs. The larger 1600-2000W ATX PSU units are extremely niche, and I don't know how you would even pull that much power without the use of multiple GPUs.
 
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Vacceo

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With an SFX or SFX-L, the width of the chamber for the PSU and reservoir should be at least 63 mm (a bit more, actually, and a little extra due to the attachment of the side panel) which is the standard width of the PSU. On that size, it´d be difficult to fit a D5 + reservoir, as those measure around 88 to 90mm in diameter (including the extra space of the mounting bracket). For an EK flat reservoir with a D5 it would be almost the same width, around 87mm. That is ATX PSU territory.

With a DDC, a flat reservoir and pump combo stays at around 51mm not including the mounting brackets. Including them and adding the heatsink, the width would stay at a bit less than 60mm, which should also provide a bit room for fittings.

Other mounting options could behind the front radiators, but that would increase the total lenght of the case by a serious amount and the point is actually reducing volume. That also detracts from airflow, logically.
 
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grsychckn

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Regarding D5 vs DDC...

Thank you for sharing, quite a lot of good information. I forked off the latest revision and now have three versions I'm working on. The difference in the last two are the support for D5/ATX vs DDC/SFX. The current volumes for both are as follows:

D5/ATX: 29L
DDC/SFX: 23.5L

That's around an 18% volume discount from the D5/ATX when going to the DDC/SFX. This is significant enough for me because this is SFF Forums and I want this to be a "small" chassis for the components inside. Correct me if you feel different, but if you are looking for a small chassis, you won't mind the sacrifice of having to use a DDC/SFX instead of the D5/ATX combo.

The only real downside is that this makes the chassis so slender that I have to drop one of the PCIe device mounts on the mainboard side. But this is an opportunity to add support for an additional PCIe device on the PSU side. The complication is in threading the PCIe riser cable through the mainboard mounting panel in a way that avoids electronic interference. Shouldn't be a problem so long as I can noodle through the positioning.

As for a DDC pump/combo, I'm thinking I'd like to create a built-in vertical mount behind the PSU. This would likely interfere with the alternative PCIe location such that it the device would need to be shorter than 180mm. I will also have a horizontal mounting location for the pump/res in the upper space (where the D5 pump combo is in the recent renders). For both, my thought here is to actually put an external hole in the top of the chassis for the purpose of having a fill location.
 
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Allhopeforhumanity

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That's around an 18% volume discount from the D5/ATX when going to the DDC/SFX. This is significant enough for me because this is SFF Forums and I want this to be a "small" chassis for the components inside. Correct me if you feel different, but if you are looking for a small chassis, you won't mind the sacrifice of having to use a DDC/SFX instead of the D5/ATX combo.

Not one bit. The Corsair SFX Platimum line is plenty of power for the vast majority of configurations; I'm not wealthy enough to have a multi-cpu rig or a pair of titans/quadros, which is about the only way I can see getting above 750w. And DDCs are definitely a step up from the tiny impellers on AIOs, so even if it is a little more high pitched than a D5, I don't think that will turn many people off.
 
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Vacceo

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Since I saw your design, I am quite fixed on using this pump and reservoir:



PWM exists to regulate the flow and thus, the noise, so it should be perfectly duable. On top of that, the pump should be close to the exhaust fans, and that means cooling it with a heatsing should be easy enough. The disposition of the motherboard should also help air to not trap the heat behind the back of the board. On the issue of less expansion for cards, I can see creators using a sound card or a video capture card, but not much beyond that, to be honest. SLI/Crossfire is becoming less and less prominent due to cost and performance.

And last but not least: 23 liters. Big for conventional under 10l SFF cases, tiny for something that can run dual radiators and full ATX boards. With the reduction to 23L, what would the external measures of the case be?
 
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