According to Corsair, it will fit a 360mm on the top. As for performance, these are the same manufacturer as all the others, the only difference is the badge and fans. As for it being enough, I'm not sure, all CPU's are different, it all depends on what the voltage you would need to hit 5.0Ghz.
If you want to connect it to the motherboard, you would need to check if it has a pump header, it's better to use a connector on your motherboard, as you will have PWM functionality, but it will quite happily run straight off the PSU too. Finally, I can't comment on Thermaltakes supplied thermal paste, but for around $5, you can't go far wrong with MX4.
