Hi all, My GFs iMac G5 has a weird problem if she leaves it sleeping over night the machine will power down when she tries to wake it up. This has only been happening since 10.4.8 was installed on it. Yesterday I did a clean Tiger install on it and the problem came back as soon as I updated to 10.4.8. It's bloody weird because if she leaves the machine on it will just keep chugging along like normal (I'm talking days here without issue) but it all goes pear shaped when the machine is put in sleep mode. If she sleeps it for a few minutes it will wake up fine, it just seems to be if it is left sleeping for a few hours. Does anyone know what could be causing this or how to go about diagnosing the problem? Any help or ideas would be great! Cheers update: I'm currently running Remember (The memtest based GUI app) on the machine to see if the memory could be at issue. Any ideas still very welcome. update: It looks like the memory is fine. http://www.xlr8yourmac.com/OSX/10.4.8_reports.html mentions heaps of people having problems with sleep issues, a lot of them are being traced back to USB devices which doesn't help me at all because the only USB devices hooked in to this Mac are an Apple Keyboard and Mighty Mouse. BRING ON 10.4.9!!! Is there anyway to down grade OS X versions?