Moving the microarchitecture from Sandy Bridge to Ivy Bridge results in a modest performance gain in terms of IPC and the clock speed increase of about 100 MHz (or 0 MHz if you count the later released Core i7-3970X part) left us with performance gains of 3-13%. Considering that SNB-E was already considered the highest performance system you could buy (for multi-threaded content), if you can gain another 10% on that in select workloads then you have an easy win."
Any major computer upgrade generally requires a full software reinstall too. No so if you heed the advice in the guide to Upgrading a Motherboard without Reinstalling. PCSTATS Tips