So are you planning to run SLI or no? (you DO knowwhat SLI is right?)
Both of those motherboards only have 1 PCI-E slot and don't support SLI.
about the PCI-E 2.0 question, ssj12 is right.
9800GT is backwards compatible with PCI-E 1.1 so it'll work on both mobos.
My 8800GTS is a PCI-E 2.0 card but works flawlessly on my mobo which only supports PCI-E 1.1
crappy old school NES games are more entertaining than next-gen games.