Hurley, with regards to the peltier.
Been there, done that, got the t-shirt. I hate to be a party pooper, but at this point in the game pelts are pretty much reserved to the Intel CPUs. Even then, I try to dissuade people from using them.
I've had an external power supply, 100+ watt TEC(s), and water-cooling rigs. Conclusion? Get yourself a good heatsink (which you have) and be happy. You'll save yourself A LOT of time, money, and sanity.
Believe me, I know. It took me more than a few hundred dollars and trips to various hardware stores to arrive at that anti-climactic conclusion some months ago.
Don't get me wrong. It was a helluva science experiment. I learned a great deal, but in the end I learned that some times you have to say Uncle.
Peltiers are just little nightmares (sometimes big nightmares) waiting to happen. I can't stress this enough, but your chances of everything going ok indefinitely are miniscule compared to the chances that the whole thing will flop and take some valuable hardware with it.
If you're brave and have cash to burn (no pun intended) go for it. Otherwise, stay away.