Long time reader, first time poster. What follows is kind of a long story, but any insight would be greatly appreciated. NONESSENTIAL BACKSTORY After working in MIS/IT for three years, I decided that I was going to leave Windows at work and let Apple into the house. This was partially because I wanted a change, and partially because I was exposed to Macs (via Max/MSP and Digital Performer and the like) in UVA's McIntire Department of Music. I got rid of my Windows PCs and welcomed a brand new MacBook Pro to the family. NEW ADDITION TO THE FAMILY Wanting to expand the family a bit, I got my hands on an ailing 867MHz Quicksilver G4 (specifications at Low End Mac) and used TechTool Pro to verify all of its hardware. Turned out that it needed a replacement hard drive. Installed that and everything worked swimmingly in Tiger. Received a second stick of 512MB PC133 memory and threw that in, and it ran even better. Dug up an NVIDIA GeForce 4 MX from a newer MDD G4 and upgraded the video as well. The interior's finishing touches were a USB 2.0 controller, an 802.11G card, and a DVD writer. Picked up a 17" Studio Display and a Pro keyboard and mouse on eBay, and I had a bona fide retro rig to make up for my Macless computing adolescence. My girlfriend really wanted a Mac, and so this would be the compromise until she could afford a MacBook. BIG(GER) CAT Now, about this time, 10.5.3 dropped. I was finally really happy with Leopard on my MacBook Pro, so one weekend I decided to see if the old G4 could keep up with the new big cat. I got Leopard installed and was fairly impressed. It wasn't the swiftest, but it worked. Grabbed the 10.5.3 update and things seemed stable. One problem: she would no longer wake from sleep! Given, Tiger took a while to wake, so I thought it just needed some time. No dice. I'd wake up the rig via mouse shake or either of the two power buttons, and after a couple of seconds of being responsive, I'd get a Perpetual Pinwheel. I waited 15 minutes a couple of times, and once or twice I even got a kernel panic. Frustrated, I yanked all of my aftermarket hardware (the USB controller, wireless card, and memory). Same problem. Swapped the video card back, and still, same problem. Thought that it may be the USB devices connected to the Studio Display's USB ports or the Studio Display itself, but same issue with a VGA CRT connected. Disconnected the keyboard and just used the mouse... same. Tried a different mouse, but no go. Waited for 10.5.4, and was once again disappointed. My last ditch efforts were resetting the PMU with the onboard switch, resetting the PRAM, and replacing the CMOS battery. None of these worked. I could either stick with 10.5.0 or run Tiger, and I really disliked having to choose. Tiger's great, but I really would like to run Leopard so my girlfriend can get to know it before she gets a MacBook. BIG BROTHER G4 AND THE UNSOLVED MYSTERY I got a new job in June, and while cleaning up some storage, I dug up some old Macs retired from my business's Creative department. Among the orphans was a 1GHz MDD G4 (specs at Low End Mac). I took the slightly beefier machine home with high hopes, and bizarrely, the story is the same. It won't wake from sleep with Leopard, either. I pulled all of the hardware I'd installed and it still pinwheeled on me. The only piece of hardware that is the same between the two G4s that I haven't already ruled out is the hard drive. It passes its SMART self-test and has passed all of the TechTool Pro tests. I can replace it for fairly cheap, and I'll probably try this last. (I can't do this at 11:00PM on a Sunday night, though, hence why I'm here!) HARD QUESTIONS 1) Does anyone here have a G4 (preferably a Quicksilver or MDD with similar specs) that's happily running 10.5.4 without any problems waking? 2) Do any grizzled technicians or Geniuses have any ideas or leads? Ask anything and everything--although I've probably done it, there's a chance I haven't, and I'm desperate. (Keeping it on all of the time is not an option. Consumes too much power and is much too noisy.) 3) As an aside, does anyone know why System Profiler would report only one processor in the MDD? From what I understand, all of the machines in this series have two processors. I've tried the Open Firmware commands to set processor access to defaults in case the second processor had been disabled for some reason, but to no avail. I look forward to your replies!