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.
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!