didn't see your original thread but here is my opinion:
Case....I'd go with an Antec, or a Lanboy
or if those are too high priced, just make sure what you
do decide on has adequate cooling and it helps to have a removeable
Mobo.
Vid cards....don't like any of the ones you listed.
ATI or Nvidia is the way to go if you can afford it.
PSU-Antec or Enermax
haven't heard anything about the Thermaltake PSU's
you're taking a chance going with that IMO.
Speakers: Z680's rock!
Klipsch does too, but go for the 5.1 instead.
I chose the Logitechs for my rig.
hope that helps.