All modern AMD and Intel processors are 64-bit and corresponding Windows versions are also on the market. It is highly recommended to use 64-bit systems (though 32-bit systems perfectly work on 64-bit processors) because in this case more than 3 Gb RAM can be employed, and today we have lots and lots of 64-bit systems, so it’s getting more and more critical.
So what are the reasons to switch to 64-bit systems, if 32-bit still work? First, it is larger address space which means that our 4 Gb Thunder Tables ™ will not bite off more memory than you’d prefer. It won’t make a crucial difference, but still… Second, low-level system programming, as in case with PPA we had to change the code to be able to inject the program into the system process and read hashes from the memory. And third, greater efficiency due to the fact that more registers have been added in 64-bit processors, but unfortunately they are only available to 64-bit programs.
We expect 64-bit Windows systems to be installed on each and every computer practically in a couple of years or so. And we are moving in this direction as well: our Proactive Password Auditor already supports 64-bit systems from its latest (January) update. Now we managed it for Proactive System Password Recovery (v.6.10 ) and we also plan to add it to Elcomsoft Wireless Security Auditor and Elcomsoft Distributed Password Recovery soon.