If it was me, and budget wasn't too big of an issue, I'd go with the i7 build, but that's just me. All three are very solid builds, and will last you quite a while. 4 cores with HT enabled is fun though.
I whould go for the i7 configuration becouse neither 5770 or 5850 are future proof(usually the GPU is the first component that get outdated). i7 has posibility of tri-channel memory and it has HT.
AMD is too expensive here for his performance+ the intel iX series are a lot more efficent then PhenomII lineup.
Now past that, why are you wanting to run linux with such graphics cards? Yes, ATi's drivers are getting better and better for faster stuff. What are you even going to use all that graphics power for under linux?
It would probably be better to go with a cheaper nvidia one anyway (just for
absolute linux support)
I dual boot linux and win7 on my gaming laptop, using windows primarily for gaming.