All textures bigger than 1024×1024 show up black on old graphic-cards. The game runs normally, but it seems to ignore those textures. It would be easy to fix – I could just make the textures smaller – but that’s not a perfect solution…
So I searched for some way of getting the maximum texture size that the system is capapble of displaying, but I found nothing.
The best solution I have so far is to have the lower res texture on by default and only if(QualitySettings.currentLevel == QualityLevel.Fantastic) I load the bigger one from the Resources into the material.
Got a better solution? Please let me know! :)