I have 2 G5 PowerMacs one Dual 2.7 and a 2.5 Quad. Neither will sleep running 10.5.8 They will with 10.5.6 but when updating to 10.5.8 the sleep feature is gone they will sleep the displays but not the machine I know of others with the same issue' I've done all the so-called remedies on the Apple support threads and none work, Has anyone here experienced this.
John
I want to share a post from Anwar Shiekh at Cube Owner on this issue it may help others>
Lost another big chunk of time on a lack of auto deep-sleep under 10.5.8
My G5 PowerMac (latest generation) would not auto deep-sleep (worked fine when done by hand) and that can cost a good chunk of money in electricity (~$100 a year as it idles around 130W, deep-sleeps at about 1/7th of this); turns out that the problem was introduced in 10.5.7 and not fixed in 10.5.8. It is probably a coincidence that the Energy Saver icon was an Edison bulb in 10.5.6, but moved to a CFL in 10.5.7. Earlier G5 PowerMac generations don't seem to suffer this fate, so this may not be of concern to Cube users.
P.S. Since writing this I have located two work arounds and one fix from the Web, all of which I have confirmed.
* Stick with 10.5.6 as mentioned above (but quite a lot changed from 10.5.6 to 10.5.8)
or
* Leave a disk in the DVD drive
I took the risk of over-riding the Apple firmware with the manufacturer's (LG), but that did not solve the problem; at least I managed not to brick the drive. However
* Using another model DVD drive (Apple System Profiler lists the problem drive as: HL-DT-ST DVD-RW GWA-4165B)
is all it took to resolve this issue. I tried an NEC 2100AD from another machine I had, and read that an LG GH22NP20 also solves the problem, and hope to try the Apple branded SONY DW-Q28A soon.
Makes one wonder about the wisdom of keeping old equipment running; $100 a year in electricity can soon add up to a new machine. Can't complain that life is not keeping me occupied.
Maybe we could start a list of Good and Bad drives with respect to this issue.
Andy