Concept EATX / SSI EEB motherboard in SFF? A Fortress inspired case idea

[chx]

SSI EEB is 305 x 330mm. EATX is a bit vague but the ROG STRIX X399-E is 305 x 269mm.

Another point: nVidia standardized on a 10.5" FE size. 1070-2080 Ti, even the Quadro P6000, all of them are 10.5". An SFX PSU is 2.5" high, added together it's the same 13" as the SSI EEB. How handy.

As the Silverstone PS13 shows, a 182mm wide case is enough for a rear 120mm fan.

Let's make it a nice square.

331 * 331 * 182 is 19940102 which happens to be the SFF definiton limit: 20L.

So take a Fortress oriented case, let's say the motherboard is on the right, the I/O cutout is on the top right. On the bottom rear left is the SFX PSU, intakes from the bottom, exhausts to the back, completely separate airflow from the rest of the case. For the biggest motherboards, it's possible it covers some of the motherboard but that's OK, it's only 125mm wide and the motherboard components are low here because they need to fit under the videocards. SFX-L easily fits. Even a TR-4 motherboard can be powered from an SFX-L PSU -- you typically get four 8 pin PCIe connectors and one of them can be converted to EPS.

Since the motherboard is only 305mm deep, we can put thin fans on the front of the chassis without bothering the motherboard. An optional Noctua NF-A12x15 on bottom of the front, the Silverstone FW181 above. And, of course, a 120mm fan on the top -- that's why we went with 182mm, remember. A Scythe Ninja fits and doesn't need any additional fans, the front and top fan will easily work and for this case it's quite ideal. Since 4U cases fit 154mm coolers and this is 4mm bigger than 4U, our cooler height is 158mm -- which just happens to be the size of the NH-U12S which also has a TR4 bracket. How handy again. That's for air cooling. if you want watercooling, well, the entire fromt half to the left of the case is totally empty and it is high enough for a 280mm radiator -- a much better option for the TR4, I must say.

I uploaded motherboard sizes to imgur kNfgcfD.png but I don't want to link it because the forum inlines it and it's huge.

 

[el01]

 

[Windfall]

That's a lot to process Lol. Maybe do some drawings?

 

[CC Ricers]

That would be amazing to see. I know at the least you can cram a SSI EEB motherboard inside a Bitfenix Prodigy or Phenom case, after some modding. What got me trying to do that was this ATX mobo case mod.

The case is large enough for EATX, though, oriented the normal way. The Bitfenix is larger at 27L though because it's about as wide as the Raijintek Metis.

 

[chx]

I am not sure about those multiple video cards, does anyone still run SLI?

 

[chx]

I worked with someone to get these concept drawings. The green box is a 120x25mm fan, the blue box is a 150x140x13 fan (I changed from the 180mm, the case is not stable if you cut 180mm out of 182mm, lol) and the purple is a 120x15mm fan.


Some notes on fans: the Raijintek Aeolus α, the Thermalright TY-14013R, the Silverstone FW141 are all 150 x 140 x 13 and mount on 120mm holes. However the Prolimatech Ultra Slim Vortex (140mm and 120mm both) and the Noctua NF-A12x15 are 15mm and I really would like to allow for those so I think will settle on 15mm fans. Also, the 120mm fan cutout needs to be 130 x 120 because of the Raijintek Aeolus β (but I just realized this when I wrote this , the drawing doesn't reflect it yet). This lower front fan is only needed for a second CPU which ought to be rare. I also now realize it is perhaps possible to have two 150 x 140 fan cutout maybe , if this case gets any further then we will see. Also, there's a possibility of using a bottom fan much like the Fortress itself which is also not on this drawing.

Anyways, these drawings show very well what I had in mind.

 

[Valantar]

Question: Won't the PSU in the bottom left corner interfere with any long AICs in the lower PCIe slots?

Also, making a 331mm-wide case for a 330mm-wide motherboard sounds ... optimistic. 0.5mm steel on each side, with zero clearance between it and the motherboard? Manufacturing tolerances would need to be impressive.

 

[chx]

It's possible a few millimetres need to be added to the height. But a few millimetres can be taken off the depth at the same time, now that the thickest fan I plan for is just 15mm.

Re PSU, I have been mulling about how the case doesn't really have a front and a back and it could be made symmetrically and then for an ATX motherboard a full ATX power supply could fit below the CPU, intake the bottom, exhausting at the purple cutout. So we would have three possible configurations:

1. up to SSI EEB MB + SFX-L PSU + 10.5" video card with the CPU at the front and the CPU fans intaking from the front. This is made possible by the card slot area clearance being only 0.6" so the motherboard easily fits between the SFX PSU and the chassis. Multiple video cards here is problematic a bit because of the outputs Silverstone provides. If one wanted to construct a second EPS plug which does not share with anything then we would need four 12V wires and the SFX-L 800 has four IDE & SATA outputs with each connector having only one 12V pin in it and two PCIe outputs with tthree 12V wires in it. So either the adapter would steal all four peripheral connectors leaving none or it would need to steal one of the PCIe connectors leaving the system with only a pair of 8 pin PCIe plugs. Maths is cruel like that. Maybe building an EPS adapter using all four and having a SATA hanging off it would work, these days and these kind of cases do not have a lot of load on those. I wish Silverstone released a 2.0 version which uses 4 pin outputs for the peripheral connectors (they only use four pins out of the six anyways) and used the reclaimed space to provide a second EPS.
2. ATX MB + short ATX PSU + any video cards with the CPU being in the back with the large CPU fan intaking from the back. This is made possible by the ATX MB being 244mm and the ATX PSU being 86mm so together they are 330mm and so no matter how high the components are on the motherboad they never meet the PSU. In another dimension: from the purple cutout to the first video card you have at least 15mm (fans) + 5mm (clearance) + 157.5mm (motherboard section) = 177.5mm so there's a few centimetres after a 140mm ATX PSU for the cables to bend before hitting a video card in the slot closest to the CPU. And, of course, there's nothing really pressing here to use that slot -- actually you want to use the slots furthest from the CPU so they are closer to the outside. More, on some motherboads this slot doesn't even exist. So really the PSU length depends on which slots are used and how -- but a 140mm always fits. If you do not use a card longer than 9.6" in the #7 slot then a 160mm fits, if the #6 doesn't overhang then a 180mm one does -- and the 170mm excellent XFX XTR comfortably fits. Notably the Akasa AK-HAD-10BK bracket to mount two 2.5" in a slot doesn't overhang and that's the primary way to mount 2.5" disks in this chassis, there's nowhere else, really. So even with a 180mm PSU you'd be able to use five slots furthest from the CPU -- with any length video card (and up to 150mm high, even). There's no problem here with the power connectors, I linked a 140mm PSU with two EPS (one and a half might be needed for TR4), four PCIe 8 pin... The only problem here is the ATX PSU would exhaust just below the main intake fan. I see two solutions: either provide a little flap which can be screwed at the top of the ATX PSU cutout which would direct the exhaust air downwards. Or in this configuration do not use a 150x140 mm fan, tell people to use a big top-down CPU cooler and provide an appropriate cutout on the side which is not shown in the images above.
3. ATX MB + SFX-L PSU + 10.5" video card + two 5.25" bays w/ the purple cutout as its opening. And then we can add a Silverstone 8 * 2.5" hot swap in 2 * 5.25". The length of this requires short cards slot #7 and perhaps even in #6 but oh well. That fan is nuts though, 3000 RPM for a few disks? That needs fixing. Just remove the fan altogether or replace with a Nexus 70mm. Details.

So there you have it. You can have a dual CPU motherboard at the cost of using a shorter -- but not too short -- video card. Even the 2080 Ti fits. It might be possible to have multiple video cards as well but I can't possibly endorse the sort of unsafe adapters that'd require. You can have an ATX motherboard and can choose between using long video cards or having a ton of hot swap bays.