Dust at the back of the case

[Shaman]

Many case manufacturers put dust filters at the front and side of the cases, but then at the back they have big unrestricted vents next to the pci slots, vented pci slot covers, etc. What is the theory here? Do they assume not much dust enters there because there aren't people and pets moving about behind the case? Or are those vents some sort of 'plan B' for when the case owner gets lazy and lets the filters clog up?

Am I the only one who has ever thought about this?

 

[leezard]

in theory intake comes in the front, exhaust out the back....an exhaust would not be taking in any dust

 

[Shaman]

in theory intake comes in the front, exhaust out the back....an exhaust would not be taking in any dust

I'm not talking about the exhaust fans at the back, but the vents around the pci slots and the vented pci slot covers many cases come with now. These vents serve more as intake than exhaust imo (unless you have a positive pressure case), what with a big exhaust fan right above them, what dust wouldn't love to enter the case through those vents?

 

[killster1]

ya i talked to dust and he said they would loveeeee to enter through my cases pci slot covers (THEY ARE WIDE OPEN) but the air current pushing out those slots just wont let the dust in so hes pissed and is now taking over my front fans filters.. (i want to just get rid of the filters but so lazy)

 

[cameron122000]

I'm not talking about the exhaust fans at the back, but the vents around the pci slots and the vented pci slot covers many cases come with now. These vents serve more as intake than exhaust imo (unless you have a positive pressure case), what with a big exhaust fan right above them, what dust wouldn't love to enter the case through those vents?

I see what you're trying to say. Technically yes, but the amount of dust that gets in that way is negligible compared to the amount you'll be pulling in from the front of your case.

 

[dystopic]

I'm not talking about the exhaust fans at the back, but the vents around the pci slots and the vented pci slot covers many cases come with now. These vents serve more as intake than exhaust imo (unless you have a positive pressure case), what with a big exhaust fan right above them, what dust wouldn't love to enter the case through those vents?

have you ever tried putting your hand next to those vents?

maybe it depends on your case, but even still. my antec 900 has two 120mm intakes, one 120mm exhaust next to the CPU, that 200mm "big boy" at the top, plus the 140mm PSU fan for exhaust as well. theoretically i should have negative pressure, yet i can still feel a faint push of air next to the PCI slots.

i also just cleaned my case after nearly 6 months of laziness. want to guess where all the dust had accumulated? i'll give you a hint: it wasn't the PCI slot vents.

 

[Shaman]

have you ever tried putting your hand next to those vents?.

I think the intake fans would have to be spinning very fast (read loud) to feel the air coming out at the back of the case. I guess most of you use intake fans, I prefer totally negative pressure cases for silence reasons, and that's almost guaranteed to have dust coming in through the vents next to the pci slots and every crack and crevice around the case.

But there are many cases with filters that come with negative pressure in stock form, the Antec SOLO is a good example: a nice filter at the front but no fans mounted there, one 120mm exhaust fan and a big honeycomb grill next to the pci slots very close to the floor. You are certain to have dust coming in through there unless you close it with tape or something else.

Same thing with the P182, which is what I have, but I replaced the vented pci slots covers with solid covers. I still get dust accumulated on the rubber gaskets for water hoses because I was too lazy to tape them up...

 

[dystopic]

noise is pretty minimal. i keep the antec fans on low except for the 200mm because it doesn't make any noise even at high speed. but our thresholds for noise tolerance are probably different.

to go back to your OP, i'm betting you're one of the only people who's ever thought about it

if you want silence, nothing beats water cooling. and as for dust, the best way to deal with that is to keep your PC on your desk (or otherwise off the floor) and vacuum and dust frequently. brushing your pets regularly helps a good deal too (i have an american longhair tabby whose fur is, i swear to god, the exact same density as air, meaning it gets errvrrwhrrr).

my guess for why case manufacturers don't put filters on the PCI slot covers would come down to one of practicality. a simple slot cover is just cut, bent aluminum. seems like adding filters to each individual one would increase the cost exponentially for what i believe is something most people wouldn't care about.

and instead of ghetto modding it with tape, why don't you just buy solid PCI slot covers? seems to me it'd be much more attractive. they're like $2 each at most.

 

[Shaman]

but our thresholds for noise tolerance are probably different.

I think so, I replaced the tricool fans because they're were too loud for me in the Low setting.

my guess for why case manufacturers don't put filters on the PCI slot covers would come down to one of practicality. a simple slot cover is just cut, bent aluminum. seems like adding filters to each individual one would increase the cost exponentially for what i believe is something most people wouldn't care about.

I also don't think it would be practical to put filters on the pci slots covers, my idea was more to use solid covers and don't put any vents near the pci slots at all.. or at least put a filter there.

and instead of ghetto modding it with tape, why don't you just buy solid PCI slot covers? seems to me it'd be much more attractive. they're like $2 each at most.

If you read my post carefully, you will see I did just that. The tape idea was for the vents next to the pci slots.. which I've seen people do before, so I guess I'm not the only one who has thought about this before after all.

 

[Shaman]

Wow I think I found the only manufacturer that believes dust can enter through the back of the case - Coolermaster!

Photo proof:

 

[DudeItsMe]

Yes, but, judging from that picture, wouldn't you say the intake is a bit laking on that case?

I'm not familiar with the workings of the Cosmos case, but I see no front intake, and possibly only a bottom (maybe) intake?

 

[Shaman]

Yes, but, judging from that picture, wouldn't you say the intake is a bit laking on that case?

I'm not familiar with the workings of the Cosmos case, but I see no front intake, and possibly only a bottom (maybe) intake?

Good observation, I looked at a few pics and it seems like that back vent is intended to work as an intake for a vga air duct..

 

[dystopic]

Good observation, I looked at a few pics and it seems like that back vent is intended to work as an intake for a vga air duct..

oh, you mean right next to where most VGA cooling solutions vent at least some of their hot air?

 

[Shaman]

Hm yeah, what did you thought I was talking about?

 

[dystopic]

that was a rhetorical/sarcastic statement. an intake vent right there is going to suck hot air back in to the case. not exclusively hot air, but higher than ambient.

 

[Shaman]

that was a rhetorical/sarcastic statement. an intake vent right there is going to suck hot air back in to the case. not exclusively hot air, but higher than ambient.

I see yeah, pretty much every case has a vent there, and in evey case it acts as an intake. Not only the hot air from the graphics card can go back in, but the hot air expelled by the 120mm fan right above it can get recycled back into the case with an added bonus: dust.

And oh yeah, if the PSU is at the bottom of the case, more hot air will go in through that vent!

 

[dystopic]

what makes you think it acts as an intake in every case? or did you mean any case rigged for negative pressure?

some cases, especially with a few mods, can have pretty significant amounts of intake. while i don't think it's totally possible to control exactly where and how air flows, consider the antec 900. it can be modded to have three 120mm intake fans. if you use the space provided for the side fan, that's a forth 120mm intake. in the a900 that space isn't a vent, but a couple of holes to run WC hoses outside the case. air is still capable of flowing through those as well as the vented PCI slot covers in either regard. i've never had to dust off the outside face of that part of my case, but dust does accumulate on the inside of those surfaces. in fact i think i'd have to work pretty hard to make those holes act as intake rather than exhaust.

 

[Shaman]

Ok true, not every case, but the majority of cases out-of-the-box (with no extra fans added) have negative pressure, so those filterless vents at the back almost always act as intake.