You have a price range of $5000?
Simple.
i7 3770k. Overclock To 4.4Ghz.

http://www.amazon.com/Intel-Core-3770K-Processor-1155/dp/B007SZ0EOW/ref=sr_1_1?ie=UTF8&qid=1341517397&sr=8-1&keywords=i7+3770K
Or. If You Don't Want An i7.
Simple.
i5 3570k. Overclock To 4Ghz+ http://www.amazon.com/Intel-Core-3570K-Processor-1155/dp/B007SZ0E1K/ref=sr_1_1?s=electronics&ie=UTF8&qid=1341517465&sr=1-1&keywords=i5+3570k