[Webscreamer]

I brought my G5 to the Apple Store the other day because my top fan of my CPU needed to be recallibrated. It ran way too fast, and reved up on simple tasks (resizing windows).

I got it back, and it helped a LOT. But, I think it could use a slight tone down again. It's going to be hard to talk the store guys into doing it again.

Is it software they boot up on and change the fans? Or how can I do it?

[Macanoid]

what kind of G5 do you have. I have a dual 2.5 with similar problems. Turns out the CPU is broken, hence the fan activity. I'm getting my CPU replaced next Monday!

[Webscreamer]

Dual 2ghz from last summer. I brought it in 2 times last fall. They told me it's normal and I should be "happy" the fans kicked in so it keeps it cool....

I got fed up with it and got the manager involved at the store and action was taken.

Very weird though... CPU is quiet when idle. But Importing songs in iTunes, Photoshop tasks, resizing windows.... all revs it up.

But I wanna know if I can change it more myself...

[blakespot]

Is it CPU activity (as might be seen in 'top' or 'Activity Monitor') that kicks in the fans or is it the thermal sensors that kick in when the CPUs actually heat up (which would have a good corrolation w/ aforementioned CPU activity)?

Which is it?



blakespot

[OzarkMtn]

I don't think they have any control over setting fan speeds. It is done with software on Apple Service Diagnostic disk. It boots into open firmware, if the fans are out of calibration they are synced to proper speed barring any hardware issues identified in the process.

[Turnpike]

if the thermal sensor on the fan is screwed up, the fans will run at high speed. you need the Apple Service Diagnostics CD to fix this. I know of no other way.

If you live close to an Apple Store, go down and just tell them to run it. Don't worry about them protesting... if you are under warranty or AppleCare, just keep demanding they do it.

[Dennis the Phantom Menace]

I'd really like to get ahold of one of those Apple Service Diagnostics CDs. My G5 has been freezing constantly and I'm 99.99999% certain that it is related to the RAM (Apple's own) overheating. Does anyone know how to get a copy of the CD??

[mjankor]

It's unlikely to be the ram overheating. There's enormous airflow through there. What it probably is is a single bad dimm.

If you have more than 2 dimms try pulling them out a set at a time and operating the machine for a while. If the crashes stop then whichever set is out of the machine is the culprit.

Most memory has a pretty good warranty and is easy to get replaced.

[Turnpike]

Originally posted by Dennis the Phantom Menace:
Does anyone know how to get a copy of the CD??

There isn't any way to get one of the CDs... I asked about this here a week or two ago because I happen to be the proud owner of an ASD G5 CD. It was left in my machine after one of several botched repairs at the Apple Store. You could try taking it in repeatedly for hardware issues and wait until they leave it in, but that could take a while. Mine was left in, specifically, after a malfunction that required a new motherboard.

As for the contents of the CD itself... it seems much like the hardware test CD that came with your computer (possibly on a separate partition of your recovery DVD). It goes a little more in-depth, I believe. Unfortunately, it isn't the be-all end-all of diagnostics and repair; I still have hardware issues, and it sees nothing wrong with the motherboard or RAM (I know I've got either a bad slot or a bad stick of RAM).

The one time it DID save me was just after I received it... they had, it seems, forgotten to run the thing. My fans were all running full blast no matter what I did. As soon as it started to boot until it slept or powered off, the fans ran. Simply booting from the CD fixed the problem -- I didn't even have to run the tests on the CD.



Also of note... I didn't see anything in there that a user could use to kill their computer with stupidity/ignorance. For this reason, I'm surprised Apple doesn't allow people to have this. The interface is much the same as the interface of the hardware test CD. The only things I can think of are:

A) Apple wants more control over repair work; this would be a great way to get non-warrantied people's money, keeping the more in-depth repair to themselves.

B) If something happens during the diagnostic (power outage, perhaps?) then it irrepairably screws your computer. I'm not sure if this is also the case with the hardware test CD. This may be a factor, but I'm nearly certain this isn't the only reason... you can screw your computer up just fine using things like Disk Utility just fine... and a power outage could cause major problems no matter what you are doing, it seems.

[Detrius]

Originally posted by Dennis the Phantom Menace:
I'd really like to get ahold of one of those Apple Service Diagnostics CDs. My G5 has been freezing constantly and I'm 99.99999% certain that it is related to the RAM (Apple's own) overheating. Does anyone know how to get a copy of the CD??

You can pay $300 for a one year membership to Apple's Technician training. That gets you access to Service Source, which is where all of the CD images are, as well as the service manuals.

However, I would like to point out that I have never seen Apple's RAM in a G5 bad. I've seen logic boards and processors, as well as third party RAM, but never Apple's. That doesn't make it impossible, but it does make it less likely. There are plenty of logic board and CPU issues that look like bad RAM.

[Dennis the Phantom Menace]

It's defintely not bad RAM. I have two more sets of RAM (1 GB a piece) in addition to my Apple RAM and all three sets exhibit the same symptoms. Up until about a month ago all three sets worked fine.
When running a temp monitor my G5 starts increasing heat until the memory controller reaches 160 F. At that point the system just freezes. This is very repeatable, so that's why I'm 99.9999% sure it's a heating issue. The thing that worries me is that the fans seem to be on even when the temp is spiraling out of control.

[Webscreamer]

I have the Diagnostics CD... it ran fine. Yet my top fan was off . . and they still calibrated it again. So if there a way to do it with the CD even if it shows no error on the fans, I would like to know.

[bstone]

Apple RAM being bad is rare but I have heard of it.

[macaddict0001]

look at the sig violator.