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MallyMal · May 8, 2005, 12:03 AM

OK, another Tiger issue...

My Rev A 12" PB is now constantly running its fan. I don't have Virex installed and never did. I already reset the PRAM and the PMU. The CPU is 75%-88% idle. So, what's left, the GPU? Could it be the GPU is overheating? It mostly turns on when I am using an external CRT monitor. It also happens when I'm plugged in without the external monitor. Boy, this is annoying.

eevyl · May 8, 2005, 02:52 AM

My Rev A 12" PB turns on the fan really often, before with Panther and now with Tiger. The little puppy is a heat machine and doing very little pumps up the hotness fast.

For what is worth, after installing Tiger and while doing the index the fan was constantly on, but after it finished it returned to "normal" operation.

Also, it is posible that with another monitor plugged in, the machine does more work (or you make the machine do more) so it heats up. Also by default while it is plugged in the CPU goes to "full speed" mode and heats up faster than in battery "reduced speed" mode.

f1000 · May 8, 2005, 09:51 AM

My Rev A and B 12" PowerBooks were/are really fan-happy as well.

tpressman · May 9, 2005, 02:09 AM

Originally Posted by f1000

My Rev A and B 12" PowerBooks were/are really fan-happy as well.

This issue popped up back with the 10.3.1 panther update. Apple modified the AppleADM103x.kext extension to turn the fan on/off at lower temps, so the fan runs more often. I can't stand this on my RevA 12".

If you get your hands on the 10.3.0 version (v.1.0.5) of AppleADM103x.kext (using Pacifist to extract it from the retail 10.3.0- install disk, etc.) and replace the Tiger version (v1.0.9) your fan issue will go away and silence will return.

It's very important that AFTER making the switch of the kext file (which will require authentication) and BEFORE restarting, that you REPAIR PERMISSIONS. If you don't the kext will fail to load and the fan won't go on at all (can you say melt down?)

kext Location: /System/Library/Extensions/AppleADM103x.kext

I wrote up this patch back when the kext was modified in 10.3.8 again. I've run Tiger for about a month (yeah, before retail release) with the old kext swapped in there and had absolutely no issues whatsoever. There was an app called Silent Night and some other patches, but I couldn't ever get them to work. My method has worked every time without issue for me.

YMMV.