Did you download the updated mobo drivers? What do you mean by "unable to login to WoW"? Does WoW launch, and does login screen lag?

This doesn't appear to be a Win7 problem, so reinstalling will get you nowhere. Did you adjust any settings in the BIOS?

Do some large file transfers from disk to disk so you can eliminate if it's a hard drive issue or not. A 1gig file should copy in seconds.

What happens when you ping 4.2.2.2