more efficient code was used in 10.4
This has been the case since 10.0 where each iteration of the OS has improved in speed over the last.
Pleased that you finally made the move and are probably thinking about why you did not go before.
You are right though, your iMac G4 would not be able to do justice to 10.5 and would not give you the same speed boost as you have seen in Tiger.
Enjoy it, I liked 10.4 and really had no problems with it.
P
Yeah, I know. I'm a day late and a dollar short, but my 17" iMac G4 is not really ready for OS 10.5. I figured Tiger will be the last OS for my computer until my baby dies and I need to buy an Intel Mac. But one question: Why is my Mac running so much faster and more efficient with 10.4.11 than it did with 10.3.9? Not only is it running faster, but all the programs, including my printer utility and web browser work better. Toast and Popcorn burn DVDs faster too. When I installed Tiger did it optimize the hard drive and get rid of scattered files?

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