I'm upgrading the G4 in my sig. and I've run into some issues installing 10.3 on it. I had no problems reinstalling the 10.2 and 10.3 upgrade disc's I got with it when I wiped the original 30 gig drive. I just bought 2x 120 gig Seagate drives to replace the original. After some screwing around I was able to get the 10.2 disc's to install and all updates. But when I run the 10.3 upgrade disc's the install fails while installing the first cd(1 of 3) and completely hoses the 10.2 install which forces me to reinstall 10.2 before trying the 10.3 disc's again. It happens with both Seagate's so i'm guessing it isn't the HD's. I'm currently using carbon copy cloner to make a duplicate copy of 10.2 on both drives so I shouldn't have to go thru the entire install again. I'm just trying to figure out were the problem is coming from. Could it be my ram upgrade (128mb-1.128gb) or possibly the install cd itself? Any advice would be appreciated.