As programs continue to advance and become better, so does the size and resources it needs increase as well. Another point worth mentioning is "time". The time involved with installing these products. In most cases you have plenty of time to install software. With proper advacned planning, we can address that with creating and installation image. That will be a future blog entry.
Autodesk has a listing of system requirements for both 32 and 64 bit, and performance recommendations. Here is the link: