If you overclock your 2500K to about 4.2GHz then honestly there is no difference between the two. The 2500K is cooler and will allow you to overclock higher than the 3770K on your current cooling.
The additional 4 threads that HT brings to the party does not make any real difference in 99% of current games. In fact I do not know of any games that use 8 threads. Your 2500K has 4 as it is.
🙂How ever from the bragging rights or epeen point of view 3770K is so sweet.
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