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what will not having DX8 compatibility do in future games? Will it make the games run slower? >>
No, just uglier. :disgust: Certain aspect of making the graphics look nicer will be missing, (eg. environment bump-mapping, pixel shading, light sources, etc, etc.)
But then there are many that won't care, so long as it's fast.
Me... I go for quality over speed, although speed must be acceptable as well.