Hi there to folks tuned in to PPC interests! Recently, I was lucky to have purchased for a very small amount,several G5s. Amoungst them were a pair of Dual Processor 2 GHz units, and one historically interesting (at least to me) 2.7 GHz unit. I had sorted the units out first by the processor speed and number info as on the sticker inside the side door. A 2.3 Ghz unit, Dual Processor, had on it's sticker "PMG5/ DP2.3/ PCI etc..", and the 2.7 GHz unit had on it's sticker "PMG5 2.7 GHz/512MB/ etc..". Which was puzzling, for I thought the 2.7 GHz speed only came as a dual processor unit, not a single. I also seemed to recall these units being the infamous Liquid Cooled horrors. Not much later, when I got to examine them in more detail, I opened this one up, and saw, not to my delight, the Delphi Liquid Cooler mackiller. That which you could see of the cooler assy was remarkably clean, but from previous experience dissassembling a totally rotted out 2.5, the coolant evils lurked further below. I also noted the presence of two heatexchangers which confirmed that it was indeed a dual. Well, I got it cheap, so if it was gone, it was gone. I powered it up, and to my surprise, it was able to boot up. My interest was climbing. I pulled out the cooling unit and saw that the processor board bottoms (the sides facing the motherboard) were in great shape with no sign of corrosion. More optimism! Continuing, separating the processor boards from the cooler assembly, I found both boards to somehow escaped the rot from the leaky cooler assy, and were, basically, with no corrosion! This puppy was a keeper! Examining the cooler assy's bottom, it was apparent the unit had just started to leak, but the coolant hadn't gotten to the boards yet. Well, almost. I found a couple crumbs ( bits of "white rice") on the boards I was able to just brush off. Now I wanted to find a suitable set of Air cooled dissipators to convert this unit. One of the the 2 Ghz units had the appropriate copper based types, and thats whats on there now. Unit is working, but the fans (not unexpectedly) ramp up at the slightest processor activity. Which I don't remember them doing when the Liq cooling assy was on. One factor could be the motherboard may have monitored the coolant's pump current draw to verify the pump's working, and now with no pump, it may be getting alarmed seeing no current draw. In any event, I want to run the Apple Hardware Test (AHT) program that is on, if web research has it right, the application disk that would have come with this computer many moons ago. But I don't know it's right number. A fellow on this site, user "reddragOn" had run the same test to get his converted to Air cooled 2.5GHz unit to run right, and used a disk, "AHT disk 2.5.8". I don't know if the 2.5.8 title came from 2.5GHz version 8, or what. If someone knows what disk I should be running to get this 2.7's thermal control running right, I would appreciate it. Also along with that, whatever Apple's scheme was for numbering these disks would be nice to know for other units as well as this one. Thanks folks!