Whether we NEED it or not, bet your ass that we'll be told its the only way to get full functionality.
Who remembers nVidia say the G80 would only work in PCI-E x16 slots? <- interesting wording!
I also saw an e-note from a GPU companys tech support to an 8800GT owner stating "Hi, thanks for your message, yes these cards are not compatible with PCI-E GEN 1.0 0r 1.1. They both will only run on PCI-E GEN 2.0 mainboards."
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