Help choosing

Hey guys i would like your opinions about this

I'm planning to buy this:
along with one of these:

Now the first one is like my top choice because of the performance (it's the 79xx chip with some fused off processors... Tahiti architecture instead of the 78xx Pitcairn) even though it will be bottlenecked to shit because i'm still rocking on a E5700 (lol). But next year i'm upgrading my cpu hopefully
BUT i hear that that GPU has heat problems. My questions are -
will that PSU suffice? will it have the necessary 2 6-pin connectors?
is there any particular difference between the 2 last ones i listed?
will i be able to fit either one of these on top of that Powercolor so it would cool better?
What would you recommend i do? I really want that extra performance it has cause i saw some benchmarks and it was really close to the 7950 as i think that that Powercolor is just a 7870 with wrong name. Should have been a 7930 :D The only issues in the reviews i saw was the heat but a friend said that it would be fixed with a good airflow in the case

Thanks in advance for any replies and suggestions