Not much reason to upgrade to these newer CPU's anyway. The improvements where performance is concerned is incredibly minor.
To give some perspective the Core i7 2600K (Sandy Bridge architecture) came out in January 2011. That's 5 years ago.
Check its scores (cpubenchmark suite):
Single Thread: 1944
Multi Thread: 8530
Now compare that to the highest end Quad Intel sell the brand new Skylake Core i7 6700K released a couple months ago.
Single Thread: 2326
Multi Thread: 11019
So it took Intel 5 years to increase single thread performance 19.6% and multi-threaded performance 29.1%. Not really that great.