I was wondering this myself.
I notice if you select Windows 7 drivers, the .net support installer for 7 only is what you are presented with.
If you select Windows 8, (puke), you get the smaller non .net installer for both 7 and 8.
I can only assume that Windows 8 has .net 4 built in.
AMD should be more clear on this and explain the situation better so users don't have to waste time wondering and trying to guess what to do here.
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