I know this is a pretty basic question, but I only know enough about computers to do what I need to do with them - I don't really understand the nuts and bolts. I'm the same with cars :-)

My old iMac G5 - probably about five years old - runs OSX 10.4. Its processor is PowerPC, rather than Intel, and now I'm getting left behind. Seems like no one makes software to go with that. So, my stupid question is: Do I need a new computer, or is there a way of installing a new processor?