i5 2500K or i5 3570K

[cluthz]

Unless the price is much different get 3570k.
A 3570k is roughly 5-8% faster at same speed, and clocked 100 MHz higher.

It is as easy getting a 2500k to 4.5 as for a 3570k to 4.2.
A 3570k is using less power, so total cost of an 3570k will always be lower,
a 2500k will use roughly 0.1KWh each day more, so depending on your electricity prices.. you get the point.

I got a 2500k just after 3570k was released, and i do not regret it, the 2500k was considerably cheaper probably because my retailer would clear some stock.

I read on forum people are still debating which CPU is the fastest, where as 3570k is faster pr clock, but 2500k does have more potential OC.
If you don't plan on OC a 3570k is better, since the 2500k must reach around 3600-3700MHz to match the stock 3570k.
In the end, both are excellent CPUs, and the two best cost efficient CPus for dolphin (and most other stuff too)

Also, as admin89 points out the 212 evo is very decent cooling for very little money.
A cooler is like the only thing that can increase your computing power by 10-25% in a $1000+ system for less than $30 :p