but for computer content it doesnt matter. 20 inches is 20 inches regardless of pixels.
Wrong, by almost nine square inches.
A 20.1" 1600x900 (16:9) display has a screen area of 444.97 mm x 250.29 mm = 111371.54 sq mm.
A 20.1" 1680x1050 (16:10) display has a screen area of 432.93 mm x 270.58 mm = 117142.2 sq mm.
117142.2 - 111371.54 = 5770.66 sq mm = 8.94454 square inches.
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