$3 Computer CPU Intake Fan Duct

Having a intake duct straight from the side of your computer case into the CPU fan can give you much better cooling than any other (air) cooling option. Instead of using air taken in from a front port, which has time to warm up from other components, the duct sucks in fresh air from the outside environment. Having an opening in the case in line with the CPU fan helps, but the air from this method is at best a mixture of some fresh air and some already from the case. There are some commercial solutions that aren't too expensive (usually $10-$20), but what I've made is definitely the right price - only $3.

Having used a collapsible fan duct for a few months, I finally decided that it was too much of a pain in the neck. First I had to modify it out of the box to fit on the fan for my CPU heatsink, then I had to duct tape it in place, and it would sometimes grind against the fan when it ran - it was a pain. I took it out and finally built something I'd been knocking around my head for a while.

This project is designed to fit an 80mm side vent, which seems to be standard on most mid-range cases nowadays. It will work with larger (or smaller) sided vents, but obviously you'll have to modify your materials, calculations, and assembly for that.

Step 1 Materials and Tools

Just a friendly reminder: Always know the proper use of any of your equipment - read any manuals and take all safety precautions. Safety glasses are recommended in just about any endeavor including tools, so if you think you need them, WEAR THEM. I am not responsible if you hurt yourself attempting this mod and I hope you don't. I managed to give myself a nice burn with my soldering iron doing another mod not long ago, which just goes to show you what can happen if you're not careful.

I used the following tools and materials in this build (there are other ways to do this, but this is what I had available to me):

Tools:

• tape measure
• calculator with trig functions
• Miter saw (can be replaced by a regular hand saw)
• Drill
• 5/32" drill bit
• 3" Hole saw (can be replaced with a scroll saw or a square saw)
• drill press (makes using the hole saw easier)
• calipers (not necessary, but helps)

Materials:

• computer case with side intake vent close to CPU fan (if you're handy enough you can make yourself a vent)
• 80mm by 80mm (3.15" x 3.15") piece of 1/4" plywood
• 5" piece of 3" PVC piping
• 4 regular case fan screws (or just two if that's all you can scrounge)
• cyanoacrylate (superglue)

I say that this project only costs $3 because that's about what it cost me. All I had to buy was the PVC and the plywood. The PVC I had cut at my local hardware store (most, if not all, will cut to length for you) and the plywood was from a much larger sheet I used in a different project. Everything else I had on hand, so your costs may vary a bit. (Especially if you have to buy any of those tools ;-)

Comments

[basejn]

I made this for my CPU before i read this. Te effect was awesome. The cpu was overclocked and it still maintaining tempriture below 40 C. About the dust ... it always intakes dust so frequently cleaning is important even without this .

[mays]

wonderfull instructable i liked this fan duct technology i must admitt that you are the only one gave me most advantages to my laptop since i recently joined you

[Ex Marine]

does it intake alot of dust

[apr1694]

yea

[baneat]

my fan is JUST out of line with my CPU.. >:(

[ReCreate]

I remember somewhere i was that they put a tube over the processor and a supercooled liquid(not sure what it was though) and overclocked it to 5000mhz !

[Yerboogieman]

Youtube, liquid nitrogen. Very cold. it was Over 5ghz

[ReCreate]

yeah i also saw it on something on tv

[djr6789]

ive benn needing this beacause my server heats up

[Yerboogieman]

at Xoxide.com

[Yerboogieman]

kool, i bought three light up fans for $3.99 each at $2.55 shipping, for all of them

[killerjackalope]

A chrome version and a clear version would be great for gamers aswell, also I noticed my miter saw has a dent in it running along (like a little guide or something) perfect for keeping round stuff straight 'n true. I didn't make this for the computer but the ideas came in handy for another item. hence the metal one, I needed a similar item for the forklift air intake because all of were nicking our arms on the fan blades while spraying ether in to the intake and cranking the starter. Extend the intake with this. Also thanks to this there's no longer a stupid rubber intake thankyou very much for reminding me of my miter saw and pipes also the trigonometry was there already...

[Toulouse]

could you get some of those pre-shaped galvanized air conditioning and vent shapes (made out of thin metal) from lowe's/home depot and do this too? i think one of those would cost about the same and do the same thing

[frazeeg]

Sure. I just find working with those more annoying and troublesome. Metal ducting is a pain ;-)

[Weissensteinburg]

I've been needing something like this...Thanks!

[LasVegas]

Great Instructable! I would have liked to see more pictures showing detail of how the duct fit inside and comparative results from before and after the installation.

[frazeeg]

I'll probably take some pictures next time I open the case. As it is it's just a pain to go under and unplug everything and open it all up, but I'll keep that in mind. There wasn't really any way to compare the before and after because I was already using a duct before I made this. I know that I got better cooling when I installed the original duct (and my CPU fan had to work less, gotta love AMD's Cool n' Quiet!). All I know is that this is much less hassle than the duct I had before and that's a good result for me :-)