Introduction: DIY Computer Fan Cooling Repair/Mod

Keeping you files cool get's difficult when the neat color-lighted fan finally goes to graveyard.

When there is nothing else wrong with the cabinet but the fan died, or if you want to add more cool to the CPU box, try this simple mod.

Step 1: Stuff You'll Need for This.


Whenever you buy any tool get the best you can afford and take care of it and it will not let you down. When buying, remember to check that it is the right type of tool required for the task.

Nibbler - I've only ever found these nibblers with a square "bite". Round and pointed triangle would be so useful. Luckily all we need here is the square. Cost is about $8-10cdn.

Screwdriver - To match screws heads.


12Vdc CPU Case Fan - You might want to get a computer case fan that comes with cables to tap into the drive power plugs. Best yet scrounge one from the computer parts dump, junk store, curb-side pickup on garbage day.

I had a CPU fan sitting in the shop so I just used it. It's a DFS122512L-PWM Kama PWM 12cm Fan; 1200rpm with only ~24.89bBA; but it does blow 52.71CFM; Sleeve Bearings with an MTBF of 30,000 hours. The connector is a 4-pin PWM (4-pin peripheral adapter included)

*Note: When 4-pin peripheral adapter is used or connected to 3-pin, the PWM function will not work. In order to take the advantage of PWM function, please use this fan with PWM function ready motherboard.

Finger guard - This is dependent on your "rug rats" status. Fans just love the taste of fresh fingertips for some reason and the screaming is just so darn anoying. If you have kids and/or pets use a real finger guard. 'Course it does mean one less learning oportunity for them, hmmmm.

Screws - Two options of sizes here, see Step 4

Step 2: Hole-ing the Panel

To keep the drill bit from "walking", use a hammer and center punch or a nail to make a starter spot.

Where you marked the fan mounting holes, drill small holes, about 1/4" diameter.

Using the largest (likely) drill bit, drill a hole somewhere within the proposed air hole. This hole must be larger than the nibbler head. You may have some luck in making a too small hole larger with a file if you are stuck.

Use work gloves for this next part for two reasons; nibblers are hard on the hands and; the sheet metal has sharp edges.

Starting at the hole, nibble the circumference of the marked air hole, as shown. Keep inside the circle.

Make sure you clean up as these nibbles are hard on sock feet and pet feet.

Step 3: Mounting the Fan

Determine the direction of flow of the fan. An arrow, usually on the side of the fan, indicates this. Mount the fan to blow into the computer case.

There are three equally good options to mounting the fan.

1) Use short coarse pointed screws, where thread goes all the way to the head, or sheet metal self-threading type screws. Pick the diameter to be just slightly larger than the mounting hole of the screw. The trick is to have the screw thick enough that the threads cut and grab the fan, but not so tight you break these mounting holes. (Method used in this "ible".)

2) Use long thin machine screws that will go completely through the fan and side panel, likely youll need a washer at the fan end. Use Ny-Lok (metal nuts made with plastic insides) nuts to prevent vibration-loosening issues.

3) Use short machine screws and mount only using the mounting holes nearest the case. Not possible on some fan designs. Look carefully at the mounting holes on the fan pictured as this fan is designed so this option will not work.

Please protect your loved ones from sticking anything into the fan. Since I have no "curious little dependants", I was able to get by with just a piece of material glued to the outside to cover the fan blades and work as a dust filter.

Step 4: Thar She Blows!

Connect the wiring depending on the new fan style.

Likely your old dead fan was wired to plug straight to the CPU card. This is likely a small 2-pin plug.

My fan came with an adapter wiring harness that connected to the drive power cable as shown.

But what about the original fan? Just leave it alone.

Put the side back on the case making sure no wires etc are rubbing. You are done. Power on to test.

Now reach your left hand way back and around and give yourself a firm pat on the back for a job well done.

Presented by Egon Pavlis