@CountRaven

You will need the Apple Service Diagnostics CD. I forget which version off hand it was to calibrate a G5. Surely there has to be an ISO somewhere around the internet. ;)

If you are still using the same matching CPUs, just be sure to put them in into the right slots again. For the most part, when I left the stock fans in it kept quiet, but time to time would spin up once it would get hotter. CPU Temps would be slightly on the higher side, but again the LCS calibration from before will spin the fans up as needed to move out some of the air. Don't worry, its all technically "active cooling" since all 4 fans down below spin. They spin the moment you power up the machine. :)

Do I recommend fan replacement? Ehhhh, If you are wanting to make the overall temperature of the CPUs cooler, then sure.

Good luck if you go that route. If you never have ripped apart the CPUs from the LCS then you may want to give it a look.

Quote:


I used this version: ASD 2.5.7

Apple Service Diagnostic is distributed to Apple Service Providers only for use with PowerBook G4 (17-inch 1.5GHz), PowerBook G4 (17-inch 1.67GHz), PowerBook G4 (15-inch 1.5/1.33GHz), PowerBook G4 (15-inch 1.67/1.5GHz), PowerBook G4 (12-inch 1.33GHz), PowerBook G4 (12-inch 1.5GHz), iBook G4 (Early 2004), iBook G4 (14-inch Early 2004), eMac (USB2.0), Power Mac G5, Power Mac G5 (June 2004 Series), Power Mac G5 (Late 2004), Power Mac G5 (Early 2005), iMac G5, iBook G4 (12-inch Late 2004), iBook G4 (14-inch Late 2004), Mac mini, and iMac G5 w/ALS (Ambient Light Sensor).

I converted my G5 2.7 tower to passive cooled one. And also i replaced all of the apple system fans too with more silent version. So now my Mos machine quiet. (of course this is relative)

Temperature with leaked liquid cooler was 85-90C
with replaced liquid cooling (PC cooling parts not apple) 62-65C
With "passive" heatsinks 70-75C (On OSX side with heavy load the highest temp was 51C, iddle 36C , avarage 42-25C with this setup.)
Of course ambient temp was around 25C

Anyway keep in mind that apple recalibration process only works under 25C

AFAIK under MOS there is no cpu switching so the central processor work with full power, under OSX there is, so thats why i think there is difference between the temperature numbers.

Anyway MOS temperature will not be correct, because i can touch the heatsinks (means it is cooler than 60C),

@Derringer

Good information. :) I been meaning to run OS X to see how the temps would vary. I did try calibration on a cooler room but still no luck. I will try again with another G5 and see if I have any luck.