I just recieved a free Power Mac G4 AGP 400mhz. Sonnet Technology makes a replacement CPU for a couple hundred bucks to bring it up to a 1.2mhz. A 2.0 USB upgrade card runs about $30. Mac Leopard OS for about $109. A couple of memory stick. Is it worth the couple of buck to bring it up to speed or and im just putting a shine on a turd? I don't know much about Mac so anything you all can advise me on would be helpful.