Foam Board Mod

[Sentinel]

FoamBoardMod

Made with 60 Second Epoxy and Foam Board.
Yes it is ghetto.

 

[HomerSapien]

Is it effective?

 

[pretzelb]

Hard to tell what you're doing since the picture is kind of blurry and there's only the one shot. I think you're trying to create a duct but here is an idea that worked well for one guy. The advantage is that you don't fight gravity and instead use it to your advantage and pull the heat up and out.

 

[Sentinel]

for me yes it expels a great deal of heat, lowering my temp by 3-4 degrees.
for $6 its a bargain

*Edit
CPU fan sucks air in then the fan out the back takes it out through the duct.
That psu idea is sweet.

 

[xbassman]

That looks pretty good!
I'd be interested to see a how to....

Good ducting is the only reason Dell can go without a cpu fan.

 

[Sentinel]

I got the idea from this mod but I modified it for my own use.

I noticed he had a missing side on his and he didnt really have a duct to centralize all the air, so I did that with mine.

I originally started out with a fan blowing in and a different setup but it made my temps raise a good 6-10 degrees.

This setup I have has lowered them around 3 - 4.

 

[xbassman]

I like it....
I haven't seen that product before......
Looks like it would be good for making a muffler for PSU exhaust also....
<starting to get ideas for my HTPC>

This stuff is available at a regular arts and crafts store? (ie Michael's)
Is it holding up to heat well?

 

[Sentinel]

yes and yes
its fun to work with

remember you need an xacto to cut with
I actually got mine at target, but it is available at officemax, pat catans, etc.
i bought the epoxy at autozone, but they also have it at home depot, wal mart etc.

the heat hasnt affected it, very stable and durable you could always coat it with some kind of insulator for noise and heat.

let me and everyone else who is interested know when you get your project started!

 

[faenix]

nice idea

 

[imported_Intolerance]

do you have a fan blowing on the main duct, like to the right of the ram.
and did you turn your fan on ur cpu backwards?

 

[KysrSose]

Sentinel,

Did the same thing and got the idea from the same source. Got a -7C difference on idle and -8C on full load. This is with 12V 60mm cpu fan undervolted to 7-5V (thermocontrolled)
With room temp 25C, air temp before cpu fan 26C, air temp inside shroud 33C (full load), 32C air @ exhaust.

i really had a poor setup to begin with though.
- 92mm fan blowing @7V out the back over cpu
- single PSU fan blowing out (70mm) - the old style 300W with only vents to take in air from case.
- stock 60mm HSF on AMD XP 2000+ running full speed 12V.
- intake was covered by a fiberglass air filter to stop cat hair and dust. No intake fan!!
Results: 46C idle 58C loaded (ooops tee hee) it does not help that i had lined the insides of the case with foam carpet underlay in my efforts to silence the PC.

folks,
The idea behind this mod is to keep the air temperature at the intake of the CPU fan as low as possible (min. room temperature) by preventing the heated air from mixing into case. The shroud effectively creates a second 'case' that puts rear case fan and the cpu fan in push/pull operation, therefor optimizing the airpressure and airflow through the heatsink i.e. closer to the rated CFM of the fan. Now if you add an intake case fan in the front, you'd have rear fan, cpu fan and front fan in series operation, and you know that directly on that path is the cpu heat sink.

The trick is to have a negative pressure inside the shroud but positive pressure inside the case. That is, you want cool air to leak into the shroud and not hot air out of the shroud. Which means the intake fan(s) should be feeding more air than what cpu and psu fan can move. While the rear case fan should move more air than cpu fan. positive case pressure keeps out dust. negative shroud pressure sucks in cool air... what more can you ask for.

My intake fan is beefed up though. With the remaining foam board, i made a 92mm x 92mm x 200mm duct, with 92mm sunon fans on both ends working in series @7V. Although this does not give me more CFM as one 92mm fan, you'll certainly have enough pressure to pull air through the dust filter. so in my setup i have 3x 92mm and a 60mm fan working in pushpull.

I see if i can take some pics.

 

[klah]

Is this the same as what Dell does? http://images.anandtech.com/re...mensionxps/open_mb.jpg

 

[KysrSose]

klah:
very similar, this design has two fans venting hot air out. There's a third one but i'm not sure where it is. The cpu heatsink has no fan apparently , unless it's that green protrusion on the lower part of the duct - centrifugal blower? and it blows from the side. The CPU heat sink has to be the first thing that the intake air flow hits.

 

[NEOSOLACE]

ahhh....here's the only foam mod you need to do!

LINK

 

[BonzaiDuck]

I like your ducted solution.

For months and months, I kept thinking that something similar to this would be effective, if you could fabricate or mold your own ducts. I remember seeing a Gateway-450 Pentium 2 which had a plastic duct screwed to the PSU intake fan -- it was a PSU arrangement where the PSU sucked in air from outside the case and then blew it down on the CPU using a black plastic duct. But in the latest generations of CPUs, this is not what we want -- we want air as cold as possible blown across the CPU heatsink, and we don't want dust-bunnies in our PSU.

What I did instead was to simply build ducts from discarded 80, 92 and 120mm fan frames. But my ducts only deliver the air to the CPU heatsink -- there is no active channel for removing it, as your mod provides. I think there's a recent computer case model from Lian Li that puts an ATX motherboard in a BTX "configuration so that the CPU is near the bottom. There is a clear plastic duct with a 120mm intake fan at the front of the case, blowing air straight through the duct across the chipset and CPU, and an exhaust fan at the rear facilitates removal of air. Similar principle. Not sure I want to flip my mobo and make my Zalman VGA heatpipe cooler totally ineffective, however.

But your "inspirational source" of the idea, in his statement of the "two principles", also gets my imprimatur because I have felt for some time that those "two principles" would be effective:

***Concentrate the cooling air only on hot items, and

***Get the hot air out immediately.

I never completely implemented the idea, because I was experimenting with different CPU heatsinks, and each would require a custom-fabricated exhaust solution.

Even so, once something is built, I investigate the possibility to keep the existing configuration and yet modify it for improvement. So for the last couple months, I have been visiting auto-parts supply stores looking for flexible "accordion" "air-cleaner intake" ducts which could be fitted to case-exhaust fans with the other end strategically placed to draw air out the bottom of heatsink fins -- the air blown down onto the heatsink by the CPU fan.

But I like your idea better. I think I could capitalize on the 120mm side-panel blowhole ducts I've built to channel outside air onto the CPU cooler, by fitting them with twin "exhaust" vents that draw air from the bottom of the CPU heatsink and exhaust it out the back -- sort of like the space-shuttle disposable launch tank and twin engines.

I think that if you have taken a sample of measurements assuring the temperature reduction of 3 to 4C, that is a significant improvement. Every little increment in temperature reduction is worth fighting for.

 

[KysrSose]

Ok I take it back.. Dell dimension XPS .. not quite the same. Under that duct is a heatpipe heatsink. those twin 90mm look like high power fans will just brute force suck (pull system) the cool air into the 'duct' through the sides and front. effectively keeping ambient air = room temp around the heat sink. It does not look like it's forcing air to pass through the heat sink - passive cooling? (i don;t know, i can't tell what the bottom of the duct looks like). I'm sure it works, just in a different way.

This foamboard mod will leave no other way for cool air to escape without passing through the fins of the HSF - well maybe through the power supply fan but that's another issue that could be 'covered'.

 

[KysrSose]

NEOSOLACE: I was going to take that route but it turned out that the foam is not available in sunsplash pink.

 

[Zap]

Ahahahahaha!!! Saw that a while back, still makes me chuckle.

 

[BonzaiDuck]

Thing is, I may try something like this. Not that I'm an inveterate copy-cat, but I'd like to see greater graphic detail on the fabrication of this foam duct. It looks like it was molded at some OEM factory -- very neatly done.

I saw another project -- probably still on the web but I don't have the URL at my fingertips -- a couple months ago.

Guy took a Zalman CNPS-7000-Cu cooler, removed the proprietary fan. Built a foam duct whose bottom end looked something like a cement trucks's rotary mixer, with a hole at the narrow end. the hole sticks down almost -- BUT NOT QUITE flush, with the copper heatsink "center". The duct bends at a right angle and meets up flush with a rear-panel fan-exhaust port, where it also holds an exhaust fan running at very low rpms. On the case exterior is a sort of "stove-pipe assembly which turns at right angles again, upward, holding another exhaust fan running at low rpm.

But the clincher -- the most curious feature of the mod -- is the use of the cut-off "wrist" of a rubber dishwashing-glove, which is fitted around the flower-petals of the Zalman, leaving air intake at two locations -- the top of the petals, and the small apertures at the bottom where the petals mate up with the heatsink base. Thus, a low-rpm, low-throughput fan causes the air to move through severely restricted apertures where air moves over the entire surface of the Zalman CNPS-7000 heatsink fins.

The builder posted thermal test results in Centigrade values. It was rather clever -- and effective. For people who swear by the Zalman CNPS-7000, such an improvement would really help in both noise and temperature reduction. Better than the original heatsink/fan itself.

 

[BonzaiDuck]

I notice that John Cinnamon, who posted the original inspiration for Sentinel's "ducted-motherboard" project, used plexi-glass for a refinement of his original foam project.

Somewhere today, I came across another forum where someone posted some worries about plexi-glass's affinity for static charge.

Except for it becoming a dust-magnet, is there any reason at all why plexi-glass would not be useful for this ducted-motherboard project?

 

[UsualSuspect]

Bonzai: i remember seeing that post with the rubber glove. the idea was force air flow at the opposite direction of heat conduction. I'm betting that the results could be improved if the air that was being blown through the fins was room temperature. if the exhausted hot air is just being 'looped back' into the fan intake, you're not getting the most out of it.

 

[BonzaiDuck]

. . . But that WAS the design of the rubber-glove mod! It sucked air from the case interior -- through the fins and out the duct that was built for it -- exhausting at the rear of the case.

I'm now re-evaluating my blow-hole duct which pulls cold air onto my XP120. If you read the other poster's evaluation "Folks! This is how this mod works", it is clear that one assumes that front intake fans pull relatively cool air to the case interior, and the ducting mod keeps that air separate from the mobo components -- allowing it to be blown into the HS fan, then ducted through the foam or plexi-glass duct to the exhaust fans and out the case. The "evaluation" noted that the intake fans should create pressure inside the case; that the HS fan should have slightly lower CFMs than the exhaust fans, and the the slight case-interior pressure would cause cold air to bleed into the duct to facilitate cooling even more.

The "evaluator" noted that this had three different fans running in "series". The intake fans, which bring in cold air, the HSF, which cools the CPU, and the exhaust fans, which remove the air after it exits the CPU HS fins.

In my design, I get the cold air, alright, for the CPU. But I had lower load temperatures when the CPU fan was pulling air from the case interior as well as the blowhole. Part of the reason for this is that the fine-mesh wire fan-filter I used as a retention mechanism for the duct also restricts airflow, even though the YS-Tech CPU fan is rated at 125.5 CFM. I'm thinking that I want to keep the blow-hole duct arrangement AND the filter, although it takes the CPU fan out of the "serial" arrangement. But directing suction from the exhaust fans on the CPU HSF and surrounding motherboard components will increase airflow through the filter and blow-hole duct, and the intake fans will assure enough pressure to keep interior (unheated) case air bleeding into Sentinel's (and Cinnamon's) ducting mod.

I'm still torn between using plexi-glass and the hobby-store foam.

 

[cryptonomicon]

Originally posted by: NEOSOLACE
ahhh....here's the only foam mod you need to do!

LINK

oh my

god.



"You gotta love that computer that looks like a hybrid between a sheep and a Meringue."

hilarious.

 

[UsualSuspect]

Bonzai: Op... we're probably not talking about the same thing with the rubber glove. This guy just talked about the heat sink mod.

Foam is easy to work with , rigid and damn cheap. My cpu unit is tucked snuggly in an ikea anton r2-d2 unit that only exposes only the front and the rear so there's no immediate access to the sides. if you have a window to show the innards with the light show, go plexi. although you foam board is also easy to decorate. We got a 20 x 24 wedding picture ( came with the package) that is printed on a foam board. imagine the possibilities ( hey how about taking a picutre of the motherboard, printing it and sticking it).

I was going to make mine froma bunch of old mouse pads. but the foam was rigid and light.

 

[BonzaiDuck]

Usual Suspect -- I appreciate your comments.

It is nice to know that the foam panels work. And I should take some pictures of my MOJO's innards and post them.

My original case-mod, started last December '03 in deliberate preparation for the build that finally got underway in June, was a compromise between what I THOUGHT I wanted in terms of case ventilation, and what I thought would be unnecessary in terms of more aggressive case modification.

This was a 1995 Gateway 2000 full-tower case, shipped to me originally as a Pentium 100 (Mhz) using an Intel "Zappa" Baby-AT mobo. Originally, there was a drive cage at the rear just under the ATX powersupply. I finally decided to expand the drive-cage offerings in the front of the case, so they run from top to bottom, and fit two 92mm LED fans as dual-twin exhausts underneath the UPS.

These fans are horizontally oriented across the case backside, unlike the two fans in the Cinnamon project. The way his fans are oriented, it makes it a little easier to duct them to the motherboard. In my case, the appeal of something more rigid like plexi-glass might make it easier to surmount the perpendicular ducting needed to mate up with the duct-mod's motherboard cover or panel. It is also possible that I could duct only one of the two fans to the mobo, and I think that would still work.

I even thought about using PVC pipe attached to the fan(s) and brought to bear on the mobo by a right angle bend. I need to think about this some more.

This is the roomiest case I've ever had, but my choice of where to put the rear fans means I should probably think about it at length and plan carefully.

I'm wondering where I can find information about "working with" plexi-glass. Some people use a saber or band-saw to cut it, and they say the material has a tendency to melt and fuse behind the saw blade. I thought I saw somewhere months and months ago how it could be heated and bent.

These things certainly make the foam idea more attractive.

Since I already have a side-panel blow-hole duct fitted to the top of the CPU fan which is 120x120mm, space between the access panel and motherboard seems to be disappearing, and it almost looks like the fans are close enough to suck out most of the CPU-heatsink-fin exhaust before it "goes anywhere else" inside the case.

Imagine. For all the trouble, there might not even be a significant improvement, except that we KNOW that restricting space over the motherboard "heat-generating" components and then sucking air swiftly from between the "mobo-duct-panel" and the mobo really helps cool them.