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PC Cases for High Dust Enviornments?
Ummagumma asks: "My computers have recently been relegated to the basement by decree of the fiancee. Problem is, the basement is carpeted (with a really old carpet), and I have two cats, which generate alot of 'fuzz'. I have had to disassemble my PC to clean the fans and heatsinks out several times now. I am looking for a case that has a built in filter of some kind, even a simple one, that wont blow the bank balance. I have found the Antec SLK3700AMB, but cannot verify that is has a filter, though I have been told it may have. I figure at least a few of you are in a similar situation, so what are you using to prevent dust and fuzz from getting into your cases? My only requirements are: At least mid-sized (full size atx board), room for 4 5.25" drives, minimum 300W powersupply, a front and rear 120mm case fan (or mountings), with a filter at least on the intake." Some of the aluminum cases from Lian Li (and I can't remember the exact model numbers) have simple filter in their front mounted fans. What other case manufacturers have such features?
Don't limit your case selection based on which have filters in the front! You can always get some filters and pop them in there. This is one of the filters I have used: http://www.directron.com/cr212nd.html -- These filters are great on dust. I have filters on all of the intake fans on my PC and have had nearly no dust in there. Just remember to clean them!!
Remember one other thing, filters are only half of the equation. To really get rid of dust you need positive airflow. What this means is, you need more air flowing in than you have flowing out. (But not too much, or it will be bad for your cooling) 10-20cfm is a good amount of extra air to have blowing in. This positive airflow creates a bit of pressure in the case which helps push dust out of the case.
It really is amazing how much filters and a bit of positive airflow can help. Try it and I guarentee as dust free a case as one can get!
My experience is that case manufacturers lack imagination. I've never seen a well-designed case, although some are better than others.
I did a search of more than 40 case manufacturers (several years ago) and the only one I was able to find that has cases with externally accessible filters is Macase. My experience is that the Macase power supplies have an extremely high failure rate, but they sell cases without power supplies.
It's great to be able to clean the filter without taking the chassis apart. Duh!! to the other manufacturers.
The Macase filters are good enough to reduce the dust by 95%. They are washable. It's necessary that the intake fan, behind the filter, has a higher airflow than the exhaust fan, inside the power supply. That way there is always positive air pressure, and air that has been filtered flows out of the leaks.
I don't know if Macase sells to the public. I've only bought wholesale from them.
Why dont you try some fan filters.
"Sic Semper Tyrannosaurus Rex."
First, make sure your case has positive pressure with respect to the outside. All your filtered fans should face in, such that any leakage is in the out direction. This is very important because otherwise, your removable media drives will act as filters, trapping the dust from the air that gets sucked in through them.
In my case, the power supply fan is the only exhaust fan. All the other fans in the case face in, and all are equipped with filters. They flow less because of the filters, but they keep up with the power supply fan, so the case is ever so slightly pressurized.
Secondly, hardware stores abound with cheap filter material. There's this great open-cell foam filter that you're supposed to wrap around your air conditioner's condenser coil to keep cottonwood fluff out. I usually just blast the thing out with the garden hose... but the filter medium is ideal for trapping large dust, and since it's intended to wrap an entire condenser, you get about 20 square feet for just a couple bucks.
There are also these little 4"x12" filters designed to be slipped behind your HVAC system's registers. Don't do that -- your forced air furnace was designed for a particular flow rate, and impeding it will cause problems. The filters, on the other hand, are just what your computer needs. They're denser material, and they work well as a second stage filter, behind the foam described above.
Ironically, about the only material at the hardware store that doesn't work very well as a computer air filter, is furnace air filter media. It's too thick for convenient mounting, and it's hard to work with.
Thirdly, the case you pick is important. Try a large tower "server" case, they usually have plenty of room for mounting extra fans, and they're better designed with respect to airflow. Filters will drastically reduce the effectiveness of each fan, so plan for at least double your usual number of fans. (Invest in some quiet ones with the fluid bearings.)
A friend recently gave me an unused computer that just happened to be built in the world's coolest case. The little fan mounting trays have plenty of space to tuck filter material inside, and everything just clips into place, no tools needed. It's a SupermicrO tower. I've been inside a lot of computer cases, and this one is by far the best-designed I've ever seen. (I have no relationship to Supermicro, I'm just impressed by their product.)
I'm going to echo the sentiment of another poster who said to elevate the machine. Get it off the floor, although I don't see a problem with setting it on a table. Just make double-sure that it's not sucking air in through openings near the bottom. I've seen lots of office desktops turn into little stationary vacuum cleaners, neatly inhaling every shred of dust that falls near them.
Good luck!
As long as the CPU isn't producing insane amounts of heat, just turn the fan in the PSU around so it sucks air instead of blowing it, and whack a plastic scouring pad (available in the dishwashing things at your nearest supermarket for a small fraction of a dollar each in bulk packs) across your new air intake. You might have to use scissors to shape the scourer aound mains plugs, switches et al, but that's easy. Feed it through the washing machine every so often - with a low-lint load - or just hand-wash it with dishwashing detergent.
If you have a motherous great room-heater for a CPU, you can add a case fan with a similar filter, or bolt another "pusher" fan over the PSU fan intake on standoffs (to allow room for dropping the scourer in between the fans).
For a multi-stage filter, get some pantyhose and flywire (aka "flyscreen", "termi-mesh" would also do, and at a pinch some coarse shadecloth) and one of those little wire baskets people use for holding garlic, potpourri, nuts and such. If you position it right, you can use a loop of wire attached to a case bolt as a hinge on one side of the basket and as a catch on the other. Stretch the pantyhose over the outside of the basket, and the flywire outside that. You will need two fans to push enough air through this arrangement.
If you have multiple computers to filter, I suggest making a single large filter assembly with a brace of fans feeding a distribution pipe, and holes on the side of that with spongy sealing tape around them to butt the PSU intakes of your boxes against (fans reversed in those, of course). An unemployed evapourative aircon picked up off the kerb during a council cleanup day and used absolutely dry can be a great start to a large filter assembly.
It helps to be able to monitor the health of all of your fans, and have a computer squeak at you if it all goes horribly wrong, which monitoring can be done optically or with a magnet on the hub not on a blade tip (think balance).
Got time? Spend some of it coding or testing
I have three of the Antec Performance II series cases(SX835II and SX1040BII) and they all have air filters on the front of the case which can be accessed without taking the case apart.
You just have to lift the case up, and they slide out from the bottom. They definately make a tremendous difference with keeping dust out of the case. I have two fans on the front pulling air in, two on the rear blowing out.
I don't know if the SLK3700AMB mentioned in this article has one. I have an SLK2600AMB and it does not. The Solution series is not nearly as nice as the Performance II series, it's not as heavy or easy to work with. However, I found the nice grey case to blend in with my television better and it houses my media computer.
- filters must be replaced regularly;
- they increase air flow turbulence and therefore noise; and
- dust builds up inside your case anyway.
Dust builds up with any airflow, so the end-all solution is to put together a system that has no airflow, meaning no fans at all.This article's a good start. Here are some guidelines:
- Remove all your case fans.
- Use awesome passive cooling heatsinks on both the CPU and video card.
- Use a case that's built with material with low heat capacitance to maximize passive system-cooling. All-plastic isn't a good idea.
- Take your power supply out of the case. Consider the Apple Cube: the power supply is external, so the unit doesn't contribute to the system temperature.
The system will run hot, but so long as it's stable, there's nothing with a warm case temperature.