I ran CocoaModem on a 350 MHz G3 All In One running 10.3 (Jaguar?) and 640MB of RAM. It was very usable. Upgrading to a 800 MHz G4 iMac and 10.4 helped a lot. So try it and you will probably be satisfied with it. An increase in speed and operating system will make a lot of difference. - Duffey -- KK6MC James Duffey Cedar Crest NM