Re: multicore support after changing cpu

If your OS is XP or the abomination that is Vista the answer is no, these natively and by default support multi-core CPUs.
However you would have to reprogram CS3 as it has few to no effective multi-core processes.
Regardless of the programming issues with CS3 a multi-core processor will be "faster" than a single core processor of the same ghz simply by offloading background sludge, of which all versions of Windows and Apple OSes are chock full, to other cores.
Speaking of sludge:
I love Itunes but here is a free tip that will noticeably speed up your computer, whether Wintel or Apptel: uninstall Itunes. Until you see the difference in performance, particularly on a single core machine, you cannot imagine how much processing power Itunes eats up even when you are not using it.

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