Here's info about my computer: Machine Model: Power Mac G4 (AGP graphics) CPU Type: PowerPC G4 (2.7) Number Of CPUs: 1 CPU Speed: 350 MHz L2 Cache (per CPU): 1 MB Memory: 1 GB Bus Speed: 100 MHz Boot ROM Version: 4.2.8f1 Have OS10.3. Use Quark (have 4.1) and other programs. Want to upgrade Quark as well as my operating system. Through this forum I now realize that I'm in difficult land if attempting to upgrade this machine. It's making weird noises, so the issue may be taken care of before I am ready! Can't afford anything new, so need either refurbished or unrefurbished used. Looking for suggestions and wisdom... Thanks!