Front Pull Bevel Chasis w/ Extra Fan?

CybeRHiDe asks: "Does anyone know of a case that uses the common front pull bezel, 3 piece sliding case, and 2 auxilary fans (one in the front bottom, and one just above the atx onboard connections)? Enlight has the pull off bezel/sliding piece case, but lacks the 2nd extra fan i've come to love on cases. Thanx!"

positive pressure is good

[Kyril]

I remember from high school (or was it college?) physics that being in front of a fan cooled you down because stopping the air molecules and making them go around you took energy out of you. I don't remember why the energy came out of you, rather than the air molecule, though...

Also, if you want to be exchanging thermal energy with air, it's best to have a lot of it. Double-pane windows have a little bit of vacuum in the middle because vacuum (the extreme of negative pressure) is such a good thermal insulator.

Looked at anything Macase?

[Static]

Not unaffordable. They come with a fan in front behind a mesh filter, and have mounting holes for a standard 80mm fan (I think) up above the ATX connectors. Also a strong power supply and high-quality metal work with no sharp edges.

Wade.

Re:Supermicro 750A for Full Tower applications

[Squeamish Ossifrage]

Absolutely. The SC-750A is far and away the best case I have ever owned. It's very solid, easy to get into, and has a Downright Unreasonable (TM) ammont of cooling potential. Two minor cautions, though: Don't expect it to come with zillions of fans. It ccomes with places to mount them, but you supply your own fans. It's large enough that, depending on what you put in and how youlay it all out, you have difficulty making cables reach.

Supermicro 750A for Full Tower applications

[Aramis]

You didn't mention what size case you were looking for. However, one popular model and my personal favorite, is the SuperMicro 750A. It features a removable front bezel, hinged, and removable right and left side panels, and a removable top panel. It comes with 80mm mounting brackets for 4 hard drive fans, 3 front fans one rear fan and one fan mounted over the CPU. Ars Technica did a great review on it:

http://arstechnica.com/reviews/1298/sc750a.html

I bought mine at www.mwave.com and it has been the best case I've ever owned.

Aramis

dansdata.com: nice fan

[Kartoffel]

The post above this provides a url to a story about putting a monster AC fan in a case. Though it's probably not a project for the novice, I tend to think that fewer big fans are better than a whole B-52's worth of small case fans. (note: the B-52 bomber was designed to have 8 smallish engines in stead of fewer big ones because at the time, there weren't any suitable large engines.)

Anyhow, while we're on the subject of monster fans... I've always wondered if it's really better to keep positive pressure inside a computer case. If you're not filtering the air, the direction of flow shouldn't make any difference, as dust will build up on everything regardless of flow direction. Yet, many people (myself included) will tell you that positive presure is good. Sure, it's *great* if you bother to filter the air; but if you don't, what difference does it make? Anyone care to shed light on this one?

let's think about this for a minute

[Kartoffel]

Although it's generally accepted that positive pressure is better, I'm afraid that people aren't really understanding why

Let's think about how dust really gets inside a computer. Consider the case as a control volume through which air and dust pass. By 'positive pressure' we mean that air enters through intake fan(s) and exits passively and/or via fans of lower flow. By 'negative pressure' the reverse is true.

Regardless of direction of flow, air passes through the case at a certain rate, carrying dust suspended in it. (secondary flow anyone? heh). Let's say that dust settles out of the air and re-enters the air at rates related to flow turbulence, velocity and the characteristics of the surface. By 'dust' i mean everything from microscopic volcanic ash particles on up to big stringy things and airborne dust bunnies.

If you don't filter the air that a fan is pushing into a positive-pressure case, the air is obviously going to be carrying dust. That dust will settle out onto any available surface at a rate approximated by my assumptions above. It's just a little bit of diffy-Q. Throw in some coefficients based on real-world experiments and you've got a decent model of how dust works.

A negative pressure case with the same volumetric flow rate as a positive case is going to be subject to the same rate of dust passing though it as a positive pressure case. I'd even hazard to guess that velocity and turbulence are about the same at most points in each case. There is no reason for a negative case to accumulate more dust *inside* itself. The large dust bunnies that get stuck on the way IN to a negative pressure case will simply get stuck on the way OUT of a positive pressure case.

The nugget of insight that i hope to convey through all this rubbish is that when people add big fans and tweak out their cases, the air inside the case becomes much more turbulent and high-speed, preventing dust from settling. Most negative pressure cases are cheapo low flow jobs; most positive pressure cases are higher-flow units that prevent dust buildup simply by being more windy inside. That's all.

Teaching Heat Transfer to EE's (and CS ppl too)

[Kartoffel]

This is an excellent time to recommend a good read: "Hot Air Rises and Heat Sinks: Everything You Know About Cooling Electronics is Wrong", by Tony Kordyban.
http://www.amazon.com/exec/obidos/ASIN/079180074 1/qid%3D933180438/002-9119807-2855832

It's witten by a mechanical engineer, yet somehow it is very enjoyable and entertaining to read. The book kind of the thermal/HVAC version of a Feynman book, with lots of funny anecdotes.

I have a poll idea too:
"How many fans are in your computer?"

[ ] 0
[ ] 1 - 3
[ ] 4 - 6
[ ] 7+
[ ] I can't tell, they're all covered with dust
[ ] Do peltiers count?

FWIW, I've got 6: 2 inhaling, 1 exhaling, and 3 impinging on extended surfaces (heatsinks)

You could add your own fan...

[jfunk]

This site has details on how to add an extra (BIG!) fan in the front of your case:

http://www.dansdata.com/hx45fan.htm [dansdata.com]

This guy also added a strap to the bottom for carrying his case around. Kind of neat.

Re:You could add your own fan...

[bpd1069]

I recently purchased a Enlight en-8900... Its a really nice server case, comes with 4 mounted 80mm fans, two mounted on the fron of the case, two mounted on the rear (directly over the atx connectors)... It was a toss up between the sc-750a and the en-8900, but aestetics did it for me. It comes standard with a 300W redundant powersupply but some venders sell it woith the single 300w, which is nice as it leaves YET another place to mount a fan above the power supply...

to sum it up:
left/right/top panels are removable
comes standard with 4 80mm fans (2 front, two rear)
front bevel
can be expanded to be joined with a file server encloseure.. has openings for wires in the case..

bpd