It's most definitely a LM171W02 panel in the iMac G4 which is definitely a 6-bit panel, you can see the specs here: https://www.panelook.com/modelsearch.php?key

It's most definitely a LM171W02 panel in the iMac G4 which is definitely a 6-bit panel, you can see the specs here: https://www.panelook.com/modelsearch.php?keyword=LM171W02&search_id=1936823 https://www.panelook.com/modelsearch.php?keyword=LM171W02&se... all of the LM171W02 panel family are 6-bit (notice the colors column lists 262k) Edit: I see you linked to the entire G4 lineup specs. The 15" is a LM151X2 and also has only 262k colors: https://www.panelook.com/modelsearch.php?keyword=LM151X2&search_id=1936844 https://www.panelook.com/modelsearch.php?keyword=LM151X2&sea... but the 20" is a LM201U04 with an IPS panel that could display millions of colors with 8 bits per channel https://www.panelook.com/modelsearch.php?keyword=LM201U04&search_id=1936870 https://www.panelook.com/modelsearch.php?keyword=LM201U04&se... so we can assume that Apple is simply using dithering to count as "millions of colors" on the lower models