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Mac Pro, Fan Problem: Fans stuck at top speed

Boddeeznutz

Boddeeznutz

macrumors newbie
Original poster
Aug 12, 2010
8
0
El Porto Surf
:mad::apple::confused:

Can anybody please help me figure this out.

2 fans on my Mac Pro are permanently stuck spinning at around their top speeds from the time the mac is turned on, until the time it is turned off or put to sleep

Here are the speeds the fans are spinning (according to iStat & smcfancontrol):
  • CPU Fan - 2781 rpm
  • PCIe/HDD Fan - 499 rpm
  • Rear Fan - 2813 rpm
  • Power Supply Fan - 599 rpm

Here are the temperatures the machine is registering (according to iStat):
  • HD1 - 32*c/90*f
  • HD2 - 32*c/90*f
  • HD3 - 42*c/108*f
  • HD4 - 41*c/106*f
  • CPU A - 24*c/74*f
  • CPU B - 25*c/76*f
  • Ambient - 21*c/70*f
  • Expansion Slot - 24*c/77*f

Here is the computer usage with just Firefox running (according to iStat & activity monitor):
*please note that this problem is here no matter which, if any, applications are running
  • User - between 6% and 20%, usually around 10%
  • System - between 1% and 10%
  • Nice - 0%
  • Idle - between 70% and 93%

Here is a summary of my machine:
  • Model Name: Mac Pro
  • Model Identifier: MacPro1,1
  • Processor Name: Dual-Core Intel Xeon
  • Processor Speed: 2.66 GHz
  • Number Of Processors: 2
  • Total Number Of Cores: 4
  • L2 Cache (per processor): 4 MB
  • Memory: 4 GB
  • Bus Speed: 1.33 GHz
  • Boot ROM Version: MP11.005C.B08
  • SMC Version (system): 1.7f10
  • Serial Number (system): G87171J6UQ2

Problems:
  • Fans are extremely loud! I can't think. I'm a musician; recording is out of the question with this problem happening.
  • Fans are going to eventually wear out, going constantly at these speeds.

Solutions I've tried, none have worked. All were done after the problem already existed:
  • Firmware is up to date
  • Machine has been thoroughly cleaned to the best of my ability. There is almost no dust anywhere i can see.
  • Machine has been visually inspected to the best of my ability. I can not find any wires, plugs, etc. that looked damaged, disconnected, etc.
  • I have removed all harddrives and booted up from a known clean Mac OS.
  • I have tried different, known good, video cards.
  • I have reset the SMC from every possible method.
  • I have reset the PRAM.
  • I have tried different optical drives.
  • I have tried smcfancontroll application, iStat, & fancontrol. These have all helped in monitoring the problem but none have been able to fix it.

Additional conditions:
  • There is plenty of good airflow around my whole workstation.
  • The air temp around my workstation is always controlled and cool.
  • I only have hardwood floors. This cuts down on the dust created by carpets.
  • I bought this computer about three weeks ago. This problem started about two weeks ago.
  • I have no idea what could have triggered this.
  • There is currently no warranty on the machine.
  • This computer was a very big purchase for me and I have almost no budget to take this machine in for professional repair.

Please, please, please send me any ideas if you can think of them. I will greatly appreciate it. I am really stuck here.
 
The temperatures look fine to me. I'm not well versed with Mac Pros, but could one of the temperature sensors have come loose causing the Mac Pro to go into a fail safe mode?
 
Intell said:
The temperatures look fine to me. I'm not well versed with Mac Pros, but could one of the temperature sensors have come loose causing the Mac Pro to go into a fail safe mode?
Click to expand...

Thank you for your response.
That definitely sounds like a possible cause but, if a sensor has come loose I don't know where to find it. I've looked for loose connections like that to the best of my ability and I haven't been able to find anything wrong.
If someone knows specifically where to look for this kind of connection problem, I will check it out right away.
 
Sounds like an SMC issue. Have you tried running the Apple Hardware Test? It's a bootable utility that should be on one of your factory restore discs.
 
I'm sorry that I can't help you, but I wanted to say that was the best newbie post I have ever seen. If only all that was a requirement for all new posts so we don't have to deal with the "it broke, fit it" mentality of many posters.
 
Not sure if it helps at all, but I'm pretty sure that the Exhaust Fan always runs 100 RPM faster than the CPU fan... so it's probably something around the CPU?
 
CaptainChunk said:
Sounds like an SMC issue. Have you tried running the Apple Hardware Test? It's a bootable utility that should be on one of your factory restore discs.
Click to expand...

Thanks for the response.
I would definitely like to try that Apple Hardware Test. However, I bought this computer on craigslist and it did not come with any of the osx discs. Do you know how or where I can run this test without a copy of the discs?
I should also mention that the OSX running on this machine is version 10.6.4
(Snow Leopard)
Thanks again.
 
You just need to reset the SMC.

Shut down the computer.
Unplug the computer's power cord and peripherals.
Press and hold the power button for 5 seconds.
Release the power button.
Attach the computers power cable.
Press the power button to turn on the computer.
 
eponym said:
You just need to reset the SMC.

Shut down the computer.
Unplug the computer's power cord and peripherals.
Press and hold the power button for 5 seconds.
Release the power button.
Attach the computers power cable.
Press the power button to turn on the computer.
Click to expand...

The OP has already reset his/her SMC.
 
Boddeeznutz said:
I would definitely like to try that Apple Hardware Test. However, I bought this computer on craigslist and it did not come with any of the osx discs. Do you know how or where I can run this test without a copy of the discs?
Click to expand...

I'm not sure but I think one can download the Apple Hardware Test from their website in disk image format. I found a list of them once, but stupidly didn't bookmark it.
 
jsurpless said:
Not sure if it helps at all, but I'm pretty sure that the Exhaust Fan always runs 100 RPM faster than the CPU fan... so it's probably something around the CPU?
Click to expand...

Thanks for the response.
That's good to know. Everything helps. I can move that much closer to figuring this out.
 
spillproof said:
I'm sorry that I can't help you, but I wanted to say that was the best newbie post I have ever seen. If only all that was a requirement for all new posts so we don't have to deal with the "it broke, fit it" mentality of many posters.
Click to expand...

Thanks a lot. I'm new to the world of Macs but I've been a troubleshooter all my life. Most notably, I was an electrician in the Navy.
I'm a little out of my scope here with this current problem but I have an idea of the kind of info I'd be looking for if I were an experienced troubleshooter in this arena.

I've got to say, I'm really glad I posted on this forum. I'm starting to feel like I might actually stand a chance at fixing this bad deal of a computer I just stuck myself with.

I coined a phrase some time ago, and I'm a big believer in it.
It's always there when I need it...

ASS!

Ask(ing) Someone Smarter!!!!
 
alphaod said:
Did you upgrade the RAM recently?
Click to expand...

As I've mentioned in the original post, I've unfortunately only had this computer for about 3 weeks.
The way it's set up right now is the way I bought it. It has fours sticks of ram (2 on each card) totaling 4GB of RAM.
I have tried running the machine with every combination of RAM I can make with these four sticks and I've tried someone else's know good RAM as well.
Nothing is leading me to think it's the RAM
I hope that helps.
Thanks for the response.
 
Intell said:
That's the site. Well then, I'd suggest you schedule a Genius Bar appointment and have them scan it. It's all free, and you don't have to have it fixed right away.
Click to expand...

Thanks. I was avoiding Apple because I know I can't afford their repair costs. I did not know, however, that they would scan it for free. I've just mad an appt for tomorrow morning. I'll be sure to update this post once they give me their assessment.

BTW, should I be worried about unlicensed software at the genius bar? As I mentioned, I bought this computer off of craigslist. It's loaded with great software and the seller said it is all legitimate, but I can not say for certain if this is all true. I can't even say for certain if the OSX (10.6.4) is legit.

Should I be worried about this, with apple's geniuses?
 
Boddeeznutz said:
Thanks. I was avoiding Apple because I know I can't afford their repair costs. I did not know, however, that they would scan it for free. I've just mad an appt for tomorrow morning. I'll be sure to update this post once they give me their assessment.

BTW, should I be worried about unlicensed software at the genius bar? As I mentioned, I bought this computer off of craigslist. It's loaded with great software and the seller said it is all legitimate, but I can not say for certain if this is all true. I can't even say for certain if the OSX (10.6.4) is legit.

Should I be worried about this, with apple's geniuses?
Click to expand...

If you have another disk laying around and someone with another mac... install a fresh copy of SL/L and pop it in and take out your current disk
 
awesome post!!!

hey i have EXACTLY the same problem with the same specs and did almost everything you said you did!!! im so glad i found this post because there is NO WAY i could of explain it better than you...

but im still with no answer to what to do to fix the problem. people please keep this post clean and straight to the point of the problem wich is... fan stuck at top speed...

and also does someone know where are the cables of the fan that sense the temperature of the cpu?? it might be that i think... somehow, maybe one got loose... worst case scenario i think it could be the logic board and in that case im BURNING or SHOOTING DOWN my mac.. there's no way im paying 800 dollars for a new logic board,

i think my mac is possessed by the devil, thats my esoteric response to the problem :cool:
 
Back in December I did a bunch of research on this. I found someone that modified Fan Control giving it access to control the PSU fan. It solved my issues. I recently reloaded my MP and Can not find this thread. :/
 
eponym said:
It's all PowerPC models. :(
Click to expand...
Now I know why you can sail all around the world and don't find AHT CDs for PPC. Thank you :)

OP: If you can't find the fault, replace all old fans with silent ones (like Noiseblocker, Be Quiet! or what ever the china men ship to the US, Scythe comes to mind), this will at least make it less noisy until you find the fault.
I don't hear anything except the hard drives in my PowerMac G4 with 80/120mm Be Quiet! USC and a 60mm SilenX, all running full-power on 12V.
 
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