[andrewas]

This should be under misc CRPGS. But to guess at an answer:

Your on a mac right? You havent gotten fed up of no chat access and bought a PC? (you really should, but lets not go there)

This phenomenon sounds like called a memory leak.

Most likley is you need to patch CIV III.

It could be because of an error in your virtual memory settings. This is a windows thing that got copied from unix. Macs have it too, but i dont know how they set it or even what they call it. Advice on all systems is the same: Add more physical RAM, leave virtual on auto.

Drivers maybe. Mac experts can help you there.

Was it you that posted you have an old version of the OS and cant afford a new one? If so it may finaly be catching up with you.