Air flow question

[xelrix]

Does the usual rules for airflow (front&bottom intake, top&rear exhaust) still applies as usual in a small case (<12L)?

Sorry for the mobile screeshot.
I'm sketching up a simple shoebox case based on the sg13.
Instead of using the front as intake, i opted for the top as intake instead. This so i could use a lowprofile cooler and have the intake to complement them.
This also allows me to further reduce the height.

Still, im not so sure about the airflow as would do well because it is so close from the roof to the motherboard, im afraid it would only create turbulamce in the area around it.

I havent made any prototype yet and i dont vape so i cant really test it out.

Sorry for the mobile screenshot as i dont have a pc right now and the app doesn't let me export to something else unless i pay.

This is left-side view (right to left) and top view (bottom to top). The smallest cube/grid is 5mm.
The "main vent" is actually the only vent in this casing. It extends from the top cover till the bottom of the left/gpu side.
The 140mm fan is the only intake.

These are the right side view and front view. In the right-side, the ssds are hidden while in the front view, the psu are hidden, for clarity.
As you can see, there's no vents on this side as i intend to allow the case to be stood either shoebox-like, or tower-like.


With that shown, what do you guys think? Will that vent and that single intake be enough?

 

[theGryphon]

That case will choke with hot air inside.

If you don't want any vents on the SSD side, then open vents under the motherboard, use the 140mm fan as exhaust and also use the fan on the C-type CPU cooler to pull air up.

One alterrnative would be to fit the tallest and biggest C-type cooler that can fit there (and especially if the fit is not tight, use/design a duct) so there is only one fan that pulls air upwards and through the top vent. It seems like Dark Rock TF would fit there nicely

EDIT: Actually with Dark Rock TF, I don't think you'd need a duct. Two fans (one on the heatsink, one on the case) would work great in tandem.

 

[xelrix]

I actually dont want to do a negative pressure because of dust.
Even the vents wouldn't be vents but just meshed cover.

I could move the ssd to the front, behind the cpu psu and extend the vent the right side too.

Somewhat irrelevant, can i use a ribbon pcie extender/riser that usually uses by miners for gaming gpu or is there specific things to consider when buyin risers for gpu that used for gaming?

 

[jtd871]

To answer your first question: If you have fans with sufficient airflow, the force of the air flow will move air through the case, independently of if you are running positive pressure (all intake), negative pressure (all exhaust), or a mix of intake/exhaust. Convective forces are too weak to matter in this situation with a sufficiently small case.

That being said, you will need to be mindful of the air flow path(s) for all your major components to avoid intaking exhaust air and having dead spots. My strong suggestion is to run a positive pressure arrangement (all intakes) with fans mounted as close to a vented side as possible and use a well-ventilated case (lots of vents on all sides). In this scenario, you bring in cooler air than is in the case and rely on air flow (volume per unit time) to displace the warm air out of the case through unobstructed vents/openings. In my situation, my case has intakes on the sides and warm air leaving by top and bottom (mostly top) panels.

If you can't get an air cooler for your CPU close to an opening to draw in fresh air, then consider using an AIO liquid cooler so you can move the heat from the CPU to where it can be more effectively cooled. You may want to have small fan(s) running inside the case for dedicated spot cooling of motherboard components in that situation.

 

[Rhialto]

I've completed a M1 build and exit of CPU heatsink is duct to the back and video card is blower type so no warm air recirculation. This mean iIntake air would normally comes from everywhere but I added a single intake fan and that way I'm able to filter dust. Maybe this can give you some ideas.

 

[BaK]

I did what @theGryphon suggests on my SG05 with an NH-C14 cooler:

The rig stays cool, but the SG05 has vents on both sides and top, and of course there is no GPU in my build.

Not like in the pics above, I have my SG05 now laying on the right side, and have noticed an increase of 2-3°C with only 2 vented sides remaining.

Somewhat irrelevant, can i use a ribbon pcie extender/riser that usually uses by miners for gaming gpu or is there specific things to consider when buyin risers for gpu that used for gaming?

Miners usually only need 1x to 16 PCIe riser cards, while you would want a 16x to 16x or at least a 8x to 16x one.

 

[theGryphon]

My recommendation was actually to have the heatsink fans as pull (the opposite direction as your pictures). Try that...

In either case, if you can turn the heatsink around 90 degrees (so that the fins are parallel to the DIMMs), it should lower the temps a little (that way the air has a direct path to/from outside through the side vents).

 

[BaK]

My recommendation was actually to have the heatsink fans as pull (the opposite direction as your pictures). Try that...

Like the OP, I prefer having a positive pressure on my cases to avoid collecting dust, thus having the fans as intake. Works fine here along with a mesh on the top side, right above the fan.

In either case, if you can turn the heatsink around 90 degrees (so that the fins are parallel to the DIMMs), it should lower the temps a little (that way the air has a direct path to/from outside through the side vents).

Hmm yes could help a little, but with such orientations the heatpipes of the C14 were interfering with either the RAMs or the back of the case, if i remember well.