Introduction: DIY PC Ambient Lighting Using Arduino and WS2812b LEDs

About: I'm an engineer.

Wanted some more depth for my gaming/movie viewing experience so here's how I installed my ambient lighting.

Before we begin, this project requires you to know how to use a soldering iron and some other basic tools. If you're not comfortable soldering, you can get somebody to do it for you... or learn how :)

Note: I'm making this after I finished the project so the pictures shown will be from the finished product.

Note2: Since this seems to be a point of confusion. This project works on computers that can run the Ambibox software. The LEDs are controlled using this software, so using this setup for regular TV viewing won't work.

Note3 (thanks to RostislavK): If you're having trouble with the arduino code, you can use the following instead:

Now that that's out of the way, let's begin with the parts list:

1. WS2812b LED strip (5m, 300 LEDs, waterproof (not necessary but I like the sleeve).


2. Arduino board. I used an Arduino Leonardo 16MHz


3. An old computer power supply. (Got from the office, if you can't find just ask around somebody's bound to have an extra one somewhere)

4. Double sided tape. I use the Wurth automotive tape since it doesn't leave any residue.

5. Soldering iron, solder, some scrap bits of wire, basic tools

Step 1: Measuring and Cutting the LED Strip

So first things first, measure the size of your monitor from behind, just to see how many LEDs from the strip you need to cut. When measuring leave about 1cm from each edge, just to make sure the strip won't show when attached to the monitor.

Once you're satisfied with your measurement, cut the LED strip to length. Each of these LEDs is individually addressable so you can cut after each LED at the marked cutting point (shown in the picture).

Go ahead and cut all 4 strips. Once done move to the next step.

Step 2: Soldering the Strip

Once you've cut all your strips to size, it's time to re-connect them to act as a single 'flexible' strip.

I used some stranded wire from a piece of Cat6 network cable. Simply solder the +5v to the next +5v rail, the DIN to the next DIN and the GND to the next GND.

Once you've done that the strip should all be connected together in 4 parts.

TIP: Unsleeve some of the rubber cover to expose the solder joints.

Important TIP: Ensure that the led strip direction arrows are pointing in the correct orientation, otherwise nothing will work.

Step 3: Connecting the Ends of the Strip

Once you're done soldering the strip together it's time to connect the ends, this part needs a bit more patience.

Solder some black wire to the GND pins at the beginning and end of the strip.

Solder some red wire to the +5v pins at the beginning and the end of the strip.

Hint: Soldering the power connection in this way allows for better power distribution in the LED strip giving more even brightness.

Solder a green/white cable to the Din at the BEGINNING of the strip (otherwise nothing will work).

Once this is done you can connect the black and red power wires to a molex connector, then to the PSU.

Caution: Make sure your connections are correct before you go to the next step as you might fry something if they're not.

Finally you can turn the PSU on by placing a jumper (I use a bit of solder) between the green and black pins of the ATX connector. This 'fools' the PSU into thinking that the computer is asking for power and thus switches it on.

Once this is done the LED strip should flash momentarily and then go off. This is normal as the LEDs have no input to tell them what to do. That's where the arduino comes in.

Step 4: Connecting the Arduino

Connect the DIN pin to pin number 3 on the arduino board. Mine came with some headers which I soldered on.

In the image I accidentally used a white wire for the ground and a black for data. Don't get confused, the data wire from the strip needs to connect to the 3rd pin on the board.

Optional: You can connect the GND pin from the arduino to the PSU GND, this is useful if you're using a separate power source from your PCs PSU.

Next connect the arduino to your PC and install the necessary drivers (if any).

Assumption: You know how to compile the code to your arduino. If not search the countless tutorials online :)

Use the arduino programmer to compile and program the arduino board with the following code:

Step 5: Setting Up the Software

Download and install ambibox

Start the software and configure your board as an 'Adalight' board using the appropriate COM port (find from device manager).

Set the Device Type to Adalight.

Set the number of zones according the quantity of LEDs you have

Finally use the wizard (click show zones first) to configure the capture zones. These zones will be what determine the colour of the light.

Once this is done you should be good to go, turn the 'use backlight' switch on and enjoy the colours :)

Step 6: Stick the Strip to the Monitor and You're Good to Go

Finally, use some double sided tape to attach the strip to the monitor. I used the Wurth stuff because it's strong.

Simply place some tape along the strip then line it up and stick it on.

Voila you've got yourself some ambient lighting for games.

Hopefully this tutorial helped you ascend.