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midiotlv

macrumors member
Original poster
Feb 5, 2008
35
0
Las Vegas, NV
I did search a few times and read quite a few 'problem posts' to see if this had been addressed, but sorry in advance if I missed it...

Occasionally, my Mac Pro's (8-core early 2008) fans will go to full speed after a shut down. I did the procedure of unplugging everything and letting it sit for 15 mins, and that seemed to work for a day or 2...but last night the problem was back.

The only solution is to hold down the power switch for 10 seconds.


Anyone else seeing this? Any hints/solutions for a Mac noob?

Thanks,

Don

P.S. I just reset PRAM -- we'll see if that has any effect.
 

Firefly2002

macrumors 65816
Jan 9, 2008
1,220
0
That's weird. By still on, do you just mean the computer's not shutting down and the fans are still on, or do you mean it takes a long time to shut down? That might be normal depending on your setup. Although it could very well be you're hanging at shutdown, dunno.

Try running some diagnostic software... I wouldn't be surprised if it were a software, not a hardware problem.

How hot is it around you right now? Hotter than usual? Any airflow problems with the case ?
 

midiotlv

macrumors member
Original poster
Feb 5, 2008
35
0
Las Vegas, NV
Firefly2002:

Thanks for your reply!

You are right, I wasn't 100% clear.

What happens is that I shut down the computer...the monitors go off...the light on the MacPro goes out...and I hear the hard-drives stop...then the fans just go full bore -- so I believe the machine is really shutting down.

I run the MacPro all day long...it is on top of my desk...no airflow restrictions....and the fans are nice and quiet all day long. (Normal..if not cooler than normal temps in my room...around 68-70 degrees F)

The problem is 'spotty'...doesn't happen on every shutdown. I 100% believe that this is a software problem (after reading about the power management reset procedures on Apple's website).

Thanks again for your response.
 

Firefly2002

macrumors 65816
Jan 9, 2008
1,220
0
Hm. I know OS 9 (Classic Mac OS) had a ShutdownCheck. Don't know if OS X has one that's similar. Could be something like that.

Sometimes when I'm shutting down my Mac (old Beige G3), it complains at me, and I just have to hit the hard power off. You might try something like DiskWarrior or TechTool Pro, if you've got it... or try using Apple's own disk repair utility, repair permissions, that sort of thing.

Unfortunately, I've only really been using Mac OS X on my old mac for a couple months (it's at home, now I'm back at school); it's an unsupported Old World Mac (Old World ROM), Tiger 10.4.9 (not Leopard), and obviously PPC not Intel. Most of my experience is also with Mac OS 9 and earlier, as well as now Windows XP. So, a lot of my suggestions are going to be... guesses. Educated guesses, but guesses nonetheless =)
 

mrcandy

macrumors regular
Nov 12, 2007
112
0
Calgary, AB Canada
Firefly2002:

Thanks for your reply!

You are right, I wasn't 100% clear.

What happens is that I shut down the computer...the monitors go off...the light on the MacPro goes out...and I hear the hard-drives stop...then the fans just go full bore -- so I believe the machine is really shutting down.

When I power down my MP it goes through the same sequence, monitors off, lights off, and hard drives stop. After that the fans continue to run for another 5-10 seconds and then there is a final click, the LEDS on the RAM risers all flash, and finally the fans stop. Sounds like your machine is occasionally having problems at this last step, locking up and going into fail safe mode with fans at full speed.

Do you have any cards in the PCI slots other than the video? If so, can you take them out and try a few power cycles to see if the problem persists.
 

rockinrocker

macrumors 65816
Aug 21, 2006
1,322
0
I did search a few times and read quite a few 'problem posts' to see if this had been addressed, but sorry in advance if I missed it...

Occasionally, my Mac Pro's (8-core early 2008) fans will go to full speed after a shut down. I did the procedure of unplugging everything and letting it sit for 15 mins, and that seemed to work for a day or 2...but last night the problem was back.

The only solution is to hold down the power switch for 10 seconds.


Anyone else seeing this? Any hints/solutions for a Mac noob?

Thanks,

Don

P.S. I just reset PRAM -- we'll see if that has any effect.

i had the same problem with my first MP (before being returned for reboot after wake problem).

you might wanna call apple....
 

midiotlv

macrumors member
Original poster
Feb 5, 2008
35
0
Las Vegas, NV
Well had a good day yesterday...no fan issues....then this morning, it happened again. The only thing I did today that I didn't do yesterday is change my screen resolution to play x-plane. I doubt that had anything to do with it, but who knows.

I unplugged everything and let it sit for a minute (the new reset for power management (SMB?) or whatever).

I will experiment more. Other than this, the MP is working great! Hope this is a problem that can be figured out w/o sending my Mac in for a new one.

Thanks for all your help and advice...and if anyone else is having this issue, please add to this thread.

-D

My config:

No extra PCI cards
8 core 2.8 (early 2008)
NVidia 8800GT
2GB std RAM + 8 GB Ram from OWC
320DB std HD + 500 GB HD (Western Digital) from OWC

Only 'weird' thing: Popped in my HP DVD burner w/Lightscribe from my old PC...works great (burns and labels discs)..but may pull it to see how it influences this fan problem.

I have repaired permissions and reset PRAM.

Thanks again for your help!

-D
 

OlBlueHair

macrumors regular
Feb 7, 2008
117
0
Mine did this once, and then every startup after that it would sit on the gray apple screen for a while then sit on a blue screen for 5 to 8 minutes before normally going to the regular desktop. I returned it because it was also doing the startup after sleep deal and got another mac pro. It also did the constant slight whirring sound (not a full on fan). The PRAM reset did nothing.

The new one is working fine except that every start has what I consider to my experience a longer than normal but by no means too long start on the gray screen. I'm so spooked about these new mac pros that I am hoping and praying this thing works as promised. I mean, when I drop 3k on something it should work, and I shouldn't have to drive an hour to exchange it and also the inconvience of re-setting up the new comp to get everything back the way it was, which takes like 4 hours, and calling apple care to transfer over to the replacement.

It's a bunch of ******** but what can you do? Use windows? Yeah right.
 

krye

macrumors 68000
Aug 21, 2007
1,606
1
USA
I thought this was by design. Think about it. You're processors are running hot. Very hot. Like 150 degrees hot. Like without the fans and heatsinks, they would melt in seconds hot. Now picture this. They are running hot all day and then you shut the power down. OK, now the fans on the CPUs are shut off. Those heatsinks alone may not be enough to effectively and efficiently cool down those very very hot CPUs. By letting the CPU fans spin a little after power down, it draws the excess heat off the CPUs and out of the case, keeping your CPUs cool and happy for many years to come.
 

Firefly2002

macrumors 65816
Jan 9, 2008
1,220
0
I thought this was by design. Think about it. You're processors are running hot. Very hot. Like 150 degrees hot. Like without the fans and heatsinks, they would melt in seconds hot. Now picture this. They are running hot all day and then you shut the power down. OK, now the fans on the CPUs are shut off. Those heatsinks alone may not be enough to effectively and efficiently cool down those very very hot CPUs. By letting the CPU fans spin a little after power down, it draws the excess heat off the CPUs and out of the case, keeping your CPUs cool and happy for many years to come.

150F isn't a big deal. Hell, I had the CPU on this 1.6 GHz Pentium M (90nm Dothan) laptop running as high as 190F after an hour of full load before I undervolted it from 1.308 to .940v. Actually, my guess is probably a little higher, since sometimes when playing Max Payne 2 it would turn off in the middle of playing. Not sure why it used every available CPU cycle whether it needed it or not, but whatever. Games like Diablo II and Quake-based games do that too (maybe OpenGL in general).

Anyway, if they couldn't make a machine capable of cooling itself well enough to shut down, they wouldn't.

And FWI, aluminum heats up and cools down very, very quickly. So do those cores on your computer. That's not really the issue.

I still say you should try using DiskWarrior or something of the sort if nothing else works.
 

midiotlv

macrumors member
Original poster
Feb 5, 2008
35
0
Las Vegas, NV
I agree..I don't think this is a 'feature'...if the fans stayed on for a few minutes then turned off, I'd consider it...

Also, I've used the Mac all day before and was able to do a 'clean' shut-down.

I'm going to try booting from CD and running the diags...see what that does for me.

Thanks again to everyone for helping.

-D
 

rockinrocker

macrumors 65816
Aug 21, 2006
1,322
0
yeah, there's no way this is a feature. my replacement just did it tonight.

i shut down, left for a few hours and when i got back the fans were still running full tilt. it'd been 3-4 hours or something!

sounds like another firmware issue or something....
 

Firefly2002

macrumors 65816
Jan 9, 2008
1,220
0
It's a very PC thing. Never really happens on Macs, but once you make the switch the the PC platform (which Apple has), you're subject to the issues that come along with it. If none of that works, yeah, I guess it's hardware related.
 

rockinrocker

macrumors 65816
Aug 21, 2006
1,322
0
yeah, this kinda sucks. i already returned one of these beasts (for the restart after sleep issue) and that's still happening too.....
 

midiotlv

macrumors member
Original poster
Feb 5, 2008
35
0
Las Vegas, NV
Resetting SMC seems to (at least for a while) fix the issue (on the new MacPro's, there is no button...you just unplug EVERYTHING and let it sit for 15 seconds)...

This works for a while, but then it seems to happen again. I'm still trying to figure out what (if anything) I'm doing causes this to happen.

I guess for now I just have to hang around for a minute after shutting down. What is the best way to let Apple know about this? Feedback link on the support page? Calling directly? (Does it make a difference?)

-D
 

Lacuna

macrumors newbie
Mar 1, 2008
3
0
New Zealand
Resetting SMC seems to (at least for a while) fix the issue (on the new MacPro's, there is no button...you just unplug EVERYTHING and let it sit for 15 seconds)...D

Until tonight, I had this exact issue with my mac pro. Fully shuts down, then a few seconds later the fan goes crazy - the only way I could solve the problem was to unplug the mac at the wall (which I've been doing for a week). The first time it happened I'd already walked out of the room when the fan went on and it ended up running all night.

After seeing your thread, I investigated resetting SMC some more. On my MP there is a very small light green button under the fourth drive bay which seems to be the said button - anyway, I pressed this and now my mac shuts down fine. Hope it continues to be fine.

Good luck, this seems to work.
 

johnnyo

macrumors newbie
Mar 9, 2008
3
0
Fans running after shutdown

I'm having the same problem. It shuts down OK and then 2 seconds later the fans come on full blast. I have to unplug it from the wall to stop it. I contacted Apple support and they don't know anything about the problem. The Mac Pro is less than a week old. I'm taking it back and see if they can fix it or give me a new one. Others seem to be having the same problem with their replacement machines. Any ideas? Is it the power supply? A problem with the updated software? Help!
 

Lacuna

macrumors newbie
Mar 1, 2008
3
0
New Zealand
I'm sad to say after posting my 'solution' a couple of posts back, the problem returned. Once again, the fans go full tilt after shutdown - sounds like a vacuum cleaner, a big one!

I can't afford to take the computer back right now as I've got a bunch of projects on the go and I need it. Really hope someone finds a fix for this issue... in the mean time unplugging at the wall after shutdown seems to be the only solution.
 

johnnyo

macrumors newbie
Mar 9, 2008
3
0
Brought the Mac in for service

As everyone knows when you bring something in to be fixed, the problem goes away when the service person looks at it. This time the computer fans came on full blast and I was able to show them what's been going on. They said they will run some tests and replace the "logic board" Hopefully Apple will become aware of this problem soon and have a fix. I'll let everyone know if the "logic board" replacement fixes the problem. I'll have it back in a few days.
 

snarlyboy

macrumors newbie
Mar 17, 2008
3
0
mac pro fans after shutdown - possible solution

Hi,

I've just been playing with my new 8-core mac pro which I've had for a week and it too exhibits this "fans-going-nuts-after-shutdown" problem.

I do have a Black Magic Design Intensity Pro HD card for final cut and a bit more searching found this link:

http://forums.creativecow.net/thread/124/868077

which seems to indicate that a new driver for the Intensity card fixes the issue. Hopefully this helps you as well. I'm about to try it now as I seem to have v 1.8.2 of the driver supposedly 1.8.3 will fix it - I'll let you all know in a week or so (I assume it would rear it's intermittent head by then) if it is fixed...

:)
 

snarlyboy

macrumors newbie
Mar 17, 2008
3
0
NZ also...

Hey Lacuna,

Just noticed you too are from NZ. Mind if I ask you where/when you got your mac pro from? Was just curious if it is the same place/batch of them as I got mine in Auckland...?

I'm also experiencing an intermittent keyboard issue (which has so far occurred in both final cut and firefox) where the aluminum keyboard seems fine but starting wigging out and repeating keys like mad and I couldn't stop it. Once it happens I can't use the keyboard until i reboot or else that repeat thing happens - and it's not a stuck key or settings in the Sys prefs either...

just curious if you too experienced issues like that... :)
 

Lacuna

macrumors newbie
Mar 1, 2008
3
0
New Zealand
I do have a Black Magic Design Intensity Pro HD card for final cut

Thanks very much! I have an Intensity card also, so it looks like that's a common factor. Hopefully this solves it.

I bought my Mac from Magnummac in Wellington - no keyboard issues by the way...

Cheers,

Josh
 

snarlyboy

macrumors newbie
Mar 17, 2008
3
0
i got mine in Auckland so its not that... must be the Intensity card software. Though be careful not to kick out a plug or anything when you install it, this 1.8.4 driver flashes the firmware of the Intensity card and then has to reboot the system twice to have the OS talk to the right card bios or whatever. You could end up with a paperweight instead of an Intensity card if you lost power during the install... :p

So far the next day the fans thing hasn't happened. I guess we'll see... :)
 

johnnyo

macrumors newbie
Mar 9, 2008
3
0
Fan Issue

I was having some problems with video output to my HD monitor using the Black Magic Pro card, so I downloaded the new drivers on Sunday. The Mac has been shutting down fine. I did bring it in for service and they replaced the Logic Board, but the fan issue was there 80% of the time. So far it looks like the Driver update solved the problem. I'll let everyone know if it happens again.:)
 
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