Hi Chris, I don't know specifically about any changes to the tolerances. The G5s have many sensors, but I guess you won't have a recorded history to peruse. There is also no utility bundles with Mac OS X for viewing you sensor readings :-(
However, you could use Activity Monitor (Mac HD > Utilities > Activity Monitor) to see if there are any "highly active" programmes running in the background of your computer. To do this, open Activity Montior and you should see a list of "Processes". Choose "All Processes" as the filter, then sort on the "% CPU" column. The items near the top of the list may offer clues. However, it is really something that you must compare against "normal", and "normal" can be different for each person (depending on peripherals, software, Internet, etc). You can expect "kernel_task" and "Activity Monitor" to appear near the top of your process lists because you are using them to generate the process list. If, on the other hand, you saw "Acme Printer Driver: 80% CPU", then you'd guess something was amiss.
