I have updated system 8.0 to 8.1. I've been useing Norton's Disk Dr. 4.0 to keep it clean & it seems like it is causing more problems than it is fixing! I finally had to low-level reformat the hard disk & reinstall everything from scratch! I haven't upgraded it again to system 8.1, so it is still on 8.0. Will Norton's utilities 4.0 work with the new system 8.5? I plan to install that soon. I use a lot of big programs like PageMaker, Photoshop, & FreeHand on a PowerTowerPro 225 PPC .