I could not find a tutorial on how to make a chipboard texture and I was fiddling with some chipboard actions so I wrote down these steps for my own reference. I'm not sure if this looks like real chipboard but it does look like chipboard on some digi-scrapping chipboard elements that I have seen.
1. Open a new canvas the size of your final chipboard element. I like to make alphas so my chipboard is 3000 x 3000 so that I can use it for a whole sheet of letters.
2. Fill the canvas with the color of your choice. I used #b5a49a.
3. Duplicate the layer (Layer > Duplicate Layer).
4. Add Noise (Filter > Noise > Add Noise).
Distribution = Gaussian
Monochromatic = Checked
5. Add Median Noise (Filter > Noise > Median).
6. Sharpen the edges (Filter > Sharpen > Sharpen Edges).
7. Use the Spatter brush stroke to turn the irregular dots into small squares that look like squashed chips (Filter > Brush Strokes > Spatter).
Smoothness = 10
8. Go to the Blend Modes (either on the layer palette or Layer > Layer Style > Blending Options) and change the blend mode for the current layer to 'Soft Light'.
9. Merge the layers and the texture is complete.
