What you are recommending will require a change of platform alltogether down the road because AMD seem to be getting further and further behin
What I am recommending is that if the OP wants to know what is the better of the two, between the i3-2100 and the Phenom II 965. I am sticking to that format, and that format only.
They themselves say they aren't tring to beat intel in performance anymore.
What is in the future is irrelevant when it comes to computers. TODAY the Phenom II overclocked performs on par with the i3 in gaming, and exceeds it in multithreaded apps, in some cases, substantially.. Beyond that, it doesn't matter what you buy today, its all "old trash" in 4-5 years just the same. Now, Intel is done with LGA 1155 socket. That means in a year, if you want to upgrade to the latest generation i5, you'll be buying a new motherboard.
Intel does not drop the price on prior generation chips. A quick search on Newegg or TigerDirect will show you that remaining LGA1156 chips are still about as expensive as they were when they were brand new, or they're just gone completely. Thats the problem with the "upgrade path" theory.
Like I said, I'm not saying one shouldn't buy an i5, but I'm sorry, it makes no sense to me that if you think you want the performance of an i5 to say "well, I think I'll get an i3 for now, and then upgrade it later". It costs you more money in the long run then if you were just to buy the right CPU to meet your needs in the first place.
The only reason I bought up the power consumpion was for OCing purposes as related to the size PSU being bought initially. You may need a larger PSU to take the PHII higher, and that will run a bit more money as well.
http://www.bit-tech.net/hardware/cpus/2011/07/13/amd-phenom-ii-x4-980-black-edition/7
Theres some power consumption data, now yes, a Phenom II 980 at 4.3GHZ, the whole system at the wall uses about 100 more watts than the 2500K. However, as far as having to buy a more expensive PSU. Most quality power supplies on the market have 500-600 watts anyway when you hit that sweet spot of good bang for the buck (I'd say around $40-$80). Its not like you'd be going out and buying a more expensive PSU than you normally would for the 2500K. I have a 750 watt PSU, but not because I actually need it. I got a good deal on it, and I bought it for the quality that Seasonic made Corsairs are known to have, I full well expect it to last me 10 years of builds.
Glad we can talk reasonably, lol. I'm not being sarcastic either, I'm seriously impressed this thread hasn't turned into a flame war yet. :lol: