10.5.6 install on eMac?

No problems here. Running on a 1.25GHz eMac with 1.5GB of RAM. I ran it for a year with 768MB of RAM and it was fine too. Just as good as Tiger was, if not better.

Your eMac will need to have a 1.0 GHz processor or faster. Leopard won't install on the oldest eMacs with 700 and 800 MHz processors. Choose About This Mac under your Apple menu to find out what speed of processor you have.

Your MacBook Pro installer discs can't be used to install 10.5 on your eMac.
Boot Camp won't work on an eMac. Alternatives for Windows exist on my FAQ*:

http://www.macmaps.com/macosxnative.html#WINTEL

Access to booting Mac OS 9 is not limited, but Classic is. You must either put 10.4.11 or earlier on a second partition, or external Firewire hard drive, if you wish to continue using Classic while having 10.5 on your system. The difference between the two is outlined in my FAQ*:

http://www.macmaps.com/macosxnative.html#CLASSIC

To install Mac OS X 10.5 if there isn't a built-in DVD drive, you must either use an equivalent age eMac to install if that equivalent age eMac has a built-in DVD drive, or an external Firewire DVD drive from http://www.macsales.com/ or http://www.xlr8yourmac.com/ that is known to be able to install 10.5. See my user tip:

http://discussions.apple.com/thread.jspa?threadID=1418365&tstart=0

- * Links to my pages may give me compensation.

If you value the auto sleep function. Don't do it. The Leopard OS runs fine. Maybe a little "clunky" but I have no real proof of that, just a feeling.
To retain the auto sleep on my eMac I'm pretty sure I can't go past Tiger 10.4.10. Also, the maximum ram which can be fitted is 1Gig (2x512).

I'm not sure what you mean by "auto sleep" not working beyond 10.4.11. It works fine here under 10.5.8.

1.25 GHz eMacs can take more RAM than the published 1GB. I have 1.5GB in mine and it works great.

My wife's eMac 1.42Ghz sleeps just fine at 10.4.11. T'is always prudent to avoid generalized statements based on a sample size of n=1.

Leopard will install on the 700 & 800Mhz eMacs and older G4's with this

LeopardAssist

http://mac.profusehost.net/leopardassist/

On the ram front. How does one ascertain if the ram can be increased over the value according to the owner manual? Are there different spec 1.25Ghz eMacs out there? How is your 1.5Gb of ram split?

The sleep issue. It began with my update to 10.4.11. It goes through the screen saver cycle to black, no image on display. So far so good. This would normally be followed by obvious signs of the computer "going to sleep". i.e. all whirring of drive, fan and the final sizzle of voltage being removed from the monitor and witnessed by the light pulsing on the front. This does't happen. Sleep can however be Scheduled in Energy Saver Prefs. It then sleeps as it should. As it does if the sleep function is accessed from the "Apple menu".

So. I purchased and installed 10.5.6 in the hope of overcoming the problem. No, still not. I installed the online updates. Still no. I went backwards with a clean install of 10.5.1 (yes, saved all my images, emails etc. and erased the hard drive). Still no. Went through all online updates again and still no.

I re installed a basic 10.4 and have updated that to 10.4.10. The Sleep facility fully functioning.
It is important to me, as I'm not the sole user of this machine that if someone walks away from it - it will Sleep. Fully. A shut down that isn't a shut down.

I am not alone with this problem. Sometimes searching for others experiencing similar difficulties (also 1.25Ghz) is a matter appropriate (or not) syntax. They are out there. Sample size of n=1+?

You say your experience is with an 1.42Ghz machine. Perhaps that makes the difference.
Gotta throw some balls in the air and see where they land.
It's a pity as this machine now can't keep pace in OS terms with my MacBook Pro i.e. synching and compatability and many iLife features. I am glad it wont run the new iMovie though!

Your experience is heartening though. Maybe I'll................

I don't understand.

You say that sleep works properly when it is selected from the Apple menu. You also say that it works correctly when scheduled.

So when exactly isn't it working?

SEE SYSTEM PREFERENCES, ENERGY SAVER.
The Sleep to which I am referring is a preset according to a specified period of inactivity. i.e. it happens automatically.
The Schedule lives behind a button in Energy Saver and allows a variety of features including Sleep according to a selected time of day.

........when the selected display sleep time has elapsed (slider control) and the "Put the computer to sleep when it is inactive for" slider is set to whatever minutes you have chosen for the sleep to occur. This is the bit that is not fully functional on my machine when running 10.4.11 or higher.

So. The Menu sleep works. The Scheduled sleep works. The timed inactivity sleep does not.

Do you use the sleep when inactive feature?

Okay, I see.

There might be some process running that is preventing your Mac from sleeping after the specified period of activity.

Try making a new user account. Log out of all other user accounts and log in to the new one. Set the sleep pref the way you want. Does your Mac still not go to sleep at the right time?

I reckon I covered that one by wiping the drive and reinstalling a brand new 10.4.0. No migration. All accounts and sundry boxes typed with fresh info. Had the bottom cover off and reset the Power Management Unit too.
For 'fun' my next step is to create another partition and install a fresh base 10.5. I might just get lucky.

Thanks for hanging around. I did reply a little while ago in the forum to someone on another thread with the same problem but now I don't seem to be able to pick that one up.

I just want to add that every time APPLE sends me software updates for emac 10.4.11 to 10.5, 10.5.6 my emac freezes or crashes. This has happened twice so today when it happened I had my emac back up in 30 min. I will never again run these updates on my 'old' emac that is in excellent condition.