Concept SFF 8 Liter High Air Flow Case Design

[iAvoe]

This is a imagined PC case designed according to existing technologies, based on Sentry 2.0, re-designed to optimize airflow

Requirements:

Remove ram stick heat sink
One maximum of 1U power supply
Optionally remove IO shield
Optionally install 90 degree 24 pin motherboard power extender for better airflow

Features:

One huge fan is better than a bunch of smaller fans
Support two 2.5'' drives
Blower has silent mode, and server mode(max processor clock speed + louder fan, cools even better than desktop)
Full size GPU
65mm tall CPU heat sink
Inverted Motherboard placement

Dimensions:

Case: 28*34*8.5(cm^3) Updated Version is even smaller
Blower: ≤170mm * ≥110mm * 85mm (Yes it's HUGE)

Warnings:

Blower spins fast enough at server mode, overclock it at your own risk
Never stick your finger into the blower, especially in server mode and overclocked

Additional features possible:

A cooling unit in the blower (example: water inside fan blade, provide cooler air than room temp)
An air channel just for motherboard VRM

Updates:

1.The processor has it's own fan with heat sink, the picture isn't very clear.

2.To take away most hot air from GPU bottom, and since we have a good 85mm thick space, we can just give the GPU a rotate from the IO phase, make it incline, fan facing more downward, then use a grill panel separate 2 rooms, most hot air can now be pushed to the area behind back plate, and it decreases the overall size!

 

[Gremlin1337]

So the blower will be 300w and that will leave 65w for cpu and 85w? Sound about right or can we get a larger watt blower in there? oh wait the 1U PSU is 450 watt min so if we increase that to like 600w then we could possibly get a 400w blower in there and still have headroom for like a Core i7-8565U and an RTX 2070. Cant wait to see this build! Also love the honeycomb look.

 

[iAvoe]

So the blower will be 300w and that will leave 65w for cpu and 85w? Sound about right or can we get a larger watt blower in there? oh wait the 1U PSU is 450 watt min so if we increase that to like 600w then we could possibly get a 400w blower in there and still have headroom for like a Core i7-8565U and an RTX 2070. Cant wait to see this build! Also love the honeycomb look.

I have to hand out this blue print since I have no resourse and time to make this real, so feel free to take it

By the way I don't think a blower really take this much power, or do they?

The honey comb was designed to be a mix of large hexagons with more smaller hexagons, but It's probably costs much to manufacture, so I didn't put much effort on it

 

[Thehack]

At 65mm cooler clearance you'd get much better performance with a top down cooler, with fins that direct towards a exhaust.

Blower coolers are loud and would perform worse, as the heat gets dumped into the rear IO instead.

You're better off putting the 1U psu where the blower is, and using the space saved to extend the height of the chassis as much you want cpu cooling performance.

 

[iAvoe]

At 65mm cooler clearance you'd get much better performance with a top down cooler, with fins that direct towards a exhaust.

Blower coolers are loud and would perform worse, as the heat gets dumped into the rear IO instead.

You're better off putting the 1U psu where the blower is, and using the space saved to extend the height of the chassis as much you want cpu cooling performance.

The real problem for sff case it's actually hot air around the heat sink than the heat sink size, although more heat is extracted from the processor temporary, the cooling capability is lost by time because of the air flow is not fast enough to extract the heat. VRMs and chipset also heats the air up though, which I feel the airflow is more important than the heat sink size

 

[Thehack]

The real problem for sff case it's actually hot air around the heat sink than the heat sink size, although more heat is extracted from the processor temporary, the cooling capability is lost by time because of the air flow is not fast enough to extract the heat. VRMs and chipset also heats the air up though, which I feel the airflow is more important than the heat sink size

What you say doesn't actually show in practice, and goes against current convention of pc building, so you'd need a bit more evidence to back it up.

1. Your drawing, you'd have to design a blower that pipes cool air to the cpu cooler. That means you need account for all socket locations. If you have it blow willy nilly:

2. It'll scatter and avoid the heatsink. Think of what is actually between the blower and the cooler: ram (of various height) 24 pin, SATA connectors.

3. It is a waste of space, because a blower isnt usually that big.

4. No one likes blowers, their sound signature is grating, and it's loud.

5. You'd have to source a blower that fits to specs.

6. Servers can actually do this because they have a clear front to rear layout. They also don't care about noise.

Notice the low rear IO and notice the orientation of the RAM slots. In a regular itx motherboard, the rear plate extends up to 52mm off the sheet meta.

So the real solution you're trying to solve:

The main problem with these layout is heat extraction. Using a top down cooler, and axial fans to extract the heat will give you much better performance I guarantee it without even any testing.

Move the 1U psu to the blower location, and populate its previous location with 80mm fans. Users install coolers like NH-L12 or Big Shuriken 2.

The Salvo S401 uses 60mm fans and shows big benefits. The reason cases like the Sentry don't do this is because they want to hit a certain volume.

Of course you can certainly follow through with your design, but I highly doubt it's effectiveness.

Heatsink size plays a big part in cooling. Surface area and airflow both contribute to cooling capacity. For the small cases, heat extraction and heatsink size are the main issues. Current fans like the Noctua NF-A12x15, being much more compact than blower, provides adequate airflow for its size.

 

[iAvoe]

What you say doesn't actually show in practice, and goes against current convention of pc building, so you'd need a bit more evidence to back it up.

1. Your drawing, you'd have to design a blower that pipes cool air to the cpu cooler. That means you need account for all socket locations. If you have it blow willy nilly:

2. It'll scatter and avoid the heatsink. Think of what is actually between the blower and the cooler: ram (of various height) 24 pin, SATA connectors.

3. It is a waste of space, because a blower isnt usually that big.

4. No one likes blowers, their sound signature is grating, and it's loud.

5. You'd have to source a blower that fits to specs.

6. Servers can actually do this because they have a clear front to rear layout. They also don't care about noise.

Notice the low rear IO and notice the orientation of the RAM slots. In a regular itx motherboard, the rear plate extends up to 52mm off the sheet meta.

So the real solution you're trying to solve:

The main problem with these layout is heat extraction. Using a top down cooler, and axial fans to extract the heat will give you much better performance I guarantee it without even any testing.

Move the 1U psu to the blower location, and populate its previous location with 80mm fans. Users install coolers like NH-L12 or Big Shuriken 2.

The Salvo S401 uses 60mm fans and shows big benefits. The reason cases like the Sentry don't do this is because they want to hit a certain volume.

Of course you can certainly follow through with your design, but I highly doubt it's effectiveness.

Heatsink size plays a big part in cooling. Surface area and airflow both contribute to cooling capacity. For the small cases, heat extraction and heatsink size are the main issues. Current fans like the Noctua NF-A12x15, being much more compact than blower, provides adequate airflow for its size.

Ok, I'll answer all your questions one by one, no problem, sorry for confusion:

The CPU has its own cooler with a fan, and a ~75mm tall space to make the heat sink large enough (e.g. SHADOW ROCK LP), which even the blower doesn't exist, this build can handle a stress test

Then, the blower takes place to improve airflow, which cools NVME SSD, RAM, VRMs and chipset

The blower is noisy is because of impression, it could go fully silent by using better bearings such as liquid/SSO, and spins much slower not just because we already have one CPU fan, but servers don't have CPU fans and their intake surface area is too small

by calculation, the air moves out from blower is less than half of ITX motherboard wide+at least 80mm tall, which the larger area is actually above the ram sticks. In extreme conditions, 90 degree ram stick converter can be manufactured but is unnecessary

The wind from blower can just go around the CPU heat sink because CPU fan already moves hot air out

In worst case, ram stick has heat sink not removed, and 24pin power didn't attached a 90 degree converter: it still has half of surface area (80mm tall 40mm wide) above the ram passes, and you can actually put 4 of 40x40x25mm (170÷40) fans on exhaust grill to pull the air out.

However, 24pin 90 degree converter is supposed to be included with this case, and manual is supposed to tell user you need to remove ram stick heat sink. I've done tons of changes to make this feels legit but it sure needs more testing to improve.

The source to get such a blower can be from heat sink manufactures like cooler master who designs cooler for other companies, or NMB who made a blower-on-top-heatsink for dell optiplex machines, which is deadly quiet and much smaller size

In your design, the hot air exhausted from PSU will cause a problem, the hot air from PSU must not to be recycled

 

[Thehack]

Ok, I'll answer all your questions one by one, no problem, sorry for confusion:

The CPU has its own cooler with a fan, and a ~75mm tall space to make the heat sink large enough (e.g. SHADOW ROCK LP), which even the blower doesn't exist, this build can handle a stress test

Then, the blower takes place to improve airflow, which cools NVME SSD, RAM, VRMs and chipset

The blower is noisy is because of impression, it could go fully silent by using better bearings such as liquid/SSO, and spins much slower not just because we already have one CPU fan, but servers don't have CPU fans and their intake surface area is too small

by calculation, the air moves out from blower is less than half of ITX motherboard wide+at least 80mm tall, which the larger area is actually above the ram sticks. In extreme conditions, 90 degree ram stick converter can be manufactured but is unnecessary

The wind from blower can just go around the CPU heat sink because CPU fan already moves hot air out

In worst case, ram stick has heat sink not removed, and 24pin power didn't attached a 90 degree converter: it still has half of surface area (80mm tall 40mm wide) above the ram passes, and you can actually put 4 of 40x40x25mm (170÷40) fans on exhaust grill to pull the air out.

However, 24pin 90 degree converter is supposed to be included with this case, and manual is supposed to tell user you need to remove ram stick heat sink. I've done tons of changes to make this feels legit but it sure needs more testing to improve.

The source to get such a blower can be from heat sink manufactures like cooler master who designs cooler for other companies, or NMB who made a blower-on-top-heatsink for dell optiplex machines, which is deadly quiet and much smaller size

In your design, the hot air exhausted from PSU will cause a problem, the hot air from PSU must not to be recycled

Very good points.

1. If the cpu cooler already has its own fan, assuming, it would make more sense to have it be immediately extracted by 80mm fans next to it, instead of using a blower that just scatters everything.

2. Adding right angle 24 pin or RAM converter kits, isn't this providing a solution by creating the problem in the first place? All these things add cost and add logistics issue for the builder and the person who manufactures the case. Sourcing a fan from coolermaster is fine and all but you have to bulk purchase.

3. 2.5SSD don't have a heat issue. They themselves are fairly low power, and for consumer use don't run at 100%. So it's really a non benefit.

4. 1U fans exhaust, instead of intake like atx or sfx so all it needs is a clear path of vents. It's a non issue. The main thing with 1U is that they are by their nature for servers and so there is no optimization for noise so people shy from it. Placing it in front of the motherboard, with the exhaust near the panel is fine.

5. Blower are noisy because the impellers are small, and they have to run at very high speeds to generate the same airflow. And bearings, which goes back to the logistics issue, using high quality blowers add more cost, along with 24 degree adapters etc. The main benefit is that they provide airflow perpendicular to the intake, but otherwise they are vastly inferior to regular fans.

 

[iAvoe]

Very good points.

1. If the cpu cooler already has its own fan, assuming, it would make more sense to have it be immediately extracted by 80mm fans next to it, instead of using a blower that just scatters everything.

2. Adding right angle 24 pin or RAM converter kits, isn't this providing a solution by creating the problem in the first place? All these things add cost and add logistics issue for the builder and the person who manufactures the case. Sourcing a fan from coolermaster is fine and all but you have to bulk purchase.

3. 2.5SSD don't have a heat issue. They themselves are fairly low power, and for consumer use don't run at 100%. So it's really a non benefit.

4. 1U fans exhaust, instead of intake like atx or sfx so all it needs is a clear path of vents. It's a non issue. The main thing with 1U is that they are by their nature for servers and so there is no optimization for noise so people shy from it. Placing it in front of the motherboard, with the exhaust near the panel is fine.

5. Blower are noisy because the impellers are small, and they have to run at very high speeds to generate the same airflow. And bearings, which goes back to the logistics issue, using high quality blowers add more cost, along with 24 degree adapters etc. The main benefit is that they provide airflow perpendicular to the intake, but otherwise they are vastly inferior to regular fans.

Just saying that it's cooling the NVME SSD, not 2.5'' SSD tho

and I feel the blower has a much larger intake area (around 140mmSq), or we can change the design to make it like LianLi O11 that just put large fans moves air into the case, pulled out by other fans

and it's taller than 1U size by default

 

[Thehack]

Right. You just need to add in a heatsink, or interface it with the chassis with adhesive thermal pad. You can vent the sheet metal near it as well. Heat issue is generally only due to very high workloads, not usually seen on most personal pc.

We generally want to create a solution for the problem, rather than have the solution be in search of problem.

The blower having a large intake area doesn't really matter. The main spec you want is airflow per noise level. Notice how most of the area on a 140mm fan is full of impellers, while only tiny little impellers are on the outside of a blower fan.

 

[iAvoe]

Right. You just need to add in a heatsink, or interface it with the chassis with adhesive thermal pad. You can vent the sheet metal near it as well. Heat issue is generally only due to very high workloads, not usually seen on most personal pc.

We generally want to create a solution for the problem, rather than have the solution be in search of problem.

The blower having a large intake area doesn't really matter. The main spec you want is airflow per noise level. Notice how most of the area on a 140mm fan is full of impellers, while only tiny little impellers are on the outside of a blower fan.

You are right, I'll take more time to redesign this case, next time you see, it would be much more legit

 

[theGryphon]

You can probably achieve a better result than a blower fan (noise and airflow) by using a 140mm fan and a custom airduct to direct the airflow towards the motherboard area.