Fresh install after CPU upgrade When installing a program on a Mac does the installer consider processor speed and number of cores in order to tailor the programs performance, and if so will upgrading processor architecture from single to dual CPUs require reinstalling the program for improved performance. 

I'm having trouble with the alignment or synchronization of sound and the visual feedback from the GUI in Apple's Logic Pro 10.2, when running more than 8 processing threads, which, now that I've installed two six core 3.46 GHz Intel Xeon 5690, is a meager count considering the 24 possible threads possible with hyperthreading.
To fix that you will probably have to reinstall Mac OS X. To do that, hold the command key when you press the power button and when the system starts up, click the option to re install Mac OS X. Hope this helps.