In this Instructable, I will be guiding you through the process of hacking and converting a clear, 120mm PWM cooling fan used in common household PCs from a single color LED to individually addressable RGB LEDs. The applications of this hack are not only limited to 120mm cooling fans, but anything your creative mind can fabricate. Accent lighting creates a unique aura, customizing the object you are illuminating and creating a profoundly different perception. In this guide, I will be modifying my computer tower to remove large amounts heat generated by the high performance CPU and GPU, in style. With the use of Texas Instruments' TLC5940 - a 16 channel PWM controller - and use of the finely crafted 5940 Arduino library - embedded design becomes extremely simplified for those of us more hardware inclined hobbyists. Additionally, we can stack TLC5940's in parallel, easily allowing us to add more fans to hack and customize all of the fans in your computer!

This is a really fun, simple, safe, and affordable weekend project. In this project, you will learn how to properly solder and tin wire leads, how to create a secure wire harness with strain relief and a sleek, manageable appearance. You will learn how to wire RGB LEDs, how to adapt common cathode or common anode LED depending on the application and hardware being used. You will learn how to configure the TLC5940 and associated hardware, as well as basic operation from a software perspective. You will finally learn how to install a CPU into a computer system, and what techniques are best for dispelling heat from within your PC tower. Finally, you will take this knowledge and gain the ability to apply accent lighting to any object your heart desires, wow to your family, and show off to your friends with your magical ambiance of mystical colorful lights.

Lets begin:

Experience Level: Beginner to Intermediate
Cost Level: Low
Estimated Build Time: 3 Hours

Parts List:

-Standard 5mm RGB LEDS (common cathode(-) is preferred but not required)
-Wire (22g)
-120mm cooling fan
-Soldering Iron
-x12 3906 General Use Transistors
-Zip Ties or Twist Ties
-Super Glue or Tape
-Arduino Uno
-x1 TLC5940
-x1 2kohm Carbon Film 1/8w (or larger) Resistor
-DC Supply (for more LEDs or higher power LED applications)
-TLC5949 Arduino Library
-USB A to B cable