i feel that is i ass a external hard-drive as well as extra ram i may possibly be able to put Leopard … call it high hopes but this is one computer im not looking forward to letting go for a while

1. Created a Disk Image of Leopard Install DVD (I used my PowerMac G4′s DL-DVD drive).

2. Installed my iMac’s Hard Drive in my PowerMac and made an extra 9Gb Partition on the iMac’s HD.

3. Restored the Leopard Install DVD Image to the 9Gb Partition (the iMac Hard Drive) which took about 5-10 minutes.

4. Hold down option key at startup and select the Leopard Install DVD Hard Drive and start up.

5. Installed Leopard to my iMac’s Larger Hard Drive partition and Shut down after install was complete.

6. Removed iMac’s Hard Drive from the PowerMac and reinstalled it to my 800Mhz iMac G4.

7. Started up Leopard for the first time on my iMac, Installed the newest updates. Runs flawlessly :)

I could have just put the iMac HD in the PowerMac and installed from the DVD drive but instead I restored the Leopard Installer DVD Image to a 9gb partition. This way I wont need my PowerMac again if something were to happen to my iMac’s Leopard Install in the future. Now I can just startup from the Installer Partition on my iMac if something goes wrong, of course I would still have to use LeopardAssist but I no longer need another Mac to install Leopard on my iMac G4 :)

Not exactly the easiest way, but it works and only took about 30 mins to do a full install, and that includes making the Installer Image and switching the drives around.

When I installed Leopard.. my iMac only had 512mb of RAM, I have since then upgraded to 2GB (yes iMac G4 800Mhz models can hold up to 2GB, though its not officially supported by apple and requires 2 different types of memory chips and bit more effort). After I installed more memory I noticed a “slight” improvement in performance but probably didn’t make much of a difference when just idling the OS.

IF anything runs slow, it is not because your iMac CPU is too slow, but more likely that the video RAM isn’t drawing graphics as fast as it used to, since previous versions of OS X don’t have nearly as many pretty designs in their GUIs as Leopard does :P

My point is, these iMac models are far from obsolete, and installing Leopard on them is still an option to consider. Us iMac G4 users are not alone!

Hope this helps :)

The great thing is that Time Machine works great and the system doesn’t seem any more sluggish than it did with Tiger.

I just got an iMac 15″ 700MHz bottom of the range. i.e. 128MB, 40GB, CD-R model lampshade in a 100% mint (as in polo) condition for a crazy bargain 18,000 Yen or about 80 pounds. The mouse was still in its original packaging!

It came with a factory restored version of OS X 10.2 which seemed to only barely ran in the 128MB originally supplied.

So, I decided to upgrade to either Tiger or Leopard and test the machine with original 40GB hard disk and just a 512MB upgrade (total 640MB). If it ran Leopoard fast enough as-is, then I’d upgrade to the full 1GB RAM, 500GB hard disk and a DVD-R (requiring a full dismantling), which should provide even better performance.

I used Firewire target disk mode and CCC to clone the HDD off my 12″ PowerBook (final) Leopard install. This took about an hour for the 10GB or so transfer.

Booted up fine, first time.

After removing various settings for bluetooth, airmac and changing the network settings so as not to double up with the PowerBook, I got to work testing.

I was surprised at the performance, expecting it to be slower than it was and the 1024 x 768 screen to be more cramped. But it runs quite well. I tried Safari, Word, Excel and Mail at the same time (a typical day’s work) and found the machine to be pleasant and entirely usable if not amazingly fast. There were none of the annoyances that I have with Tiger on my stock G4 Cube, for example.

I found that the 10.5.2 system install was waiting so I installed that plus graphics update 1.0 and a few other queued updates.

Probably subjective, but I found the whole thing to be even smoother and more responsive. For example, clicking on the finder icon in the dock brings up any open finder windows almost instantaneously over whatever you’re doing at the time.

A lot better than my stock cube with 1.5GB RAM and Tiger.

I’d like to test it out with Tiger for a speed comparison, but quite frankly, besides the lack of awaking from sleep, it’s running so smooth that I don’t see the point.

In conclusion

Install from cloned PowerBook HDD using CCC was effortless and took an hour or so for a 10GB install.
Leopard runs trouble free, with so far no crashes or random stuff happening (apart from wake from sleep).
10.5.2 upgrade and Graphics Update 1.0 work wonderfully.
640MB RAM and 40GB HDD gives more than adequate performance for Surfing, iTunes, Office 2004 multitasking.
Remaining Niggles:

Awakes from sleep with screen artifacts (but at least it can be gracefully reset since the OSX10.5.2 / GU1.0 updates).
Boot up is slow. Haven’t timed it, but it’s slow.
Logging in is slow.
Of the above complaints, only the first is a real one, since, once logged in, everything is hunky dory.

I think I’ll keep the machine like this for a week or to so that I can appreciate the upgrade when I perform it.

I wonder how much faster the Seagate 500GB HDD and extra 386MB of RAM will make it…

http://forums.macnn.com/90/mac-os-x/351987/leopard-on-800mhz-g4-imac/