For starters CS3 is a 32bit Application can not even access 4GB of Rams and in CS3 there is no GPU support, ACR is at version 4.6. On the bright side is it was a very good version of Photoshop has some old features that have been removed and does not have the bugs introduced in the newer versions of Photoshop. Old software is better off use on machines running the OS version the software was released for.
