17" iMac G5 2GHz (ALS but no iSight) runs hot and LOUD fans

Hi all,
I love my iMac. I've had it for nearly 8 months now. From day 1, I've been surprised by how loud it is under any significant CPU load. Unfortunately for me, I have waited until I'm well out of my phone support window to do anything about it. I have not yet purchased AppleCare.
As I type this, my CPU temp is 70 degrees C and fan is running at 2600 RPM, running nothing beyond the browser in which I'm typing. Should I attempt to work in iMovie and render said work to DVD (the reason I bought the machine), CPU temp will climb to ~76 and fan speed jumps to 4600-4800 RPM. At this speed, the noise is unbearable...but it is annoying even when idle.
Can any of you with this model of 17" iMac comment on your experience? Do these numbers and this experience sound normal? I know I'm not alone in this complaint, but I can't tell how widespread the problem is or whether my machine is normal or defective. I've been told by my local service center (CompUSA) that every single 17" iMac of this revision runs hot and has loud fans, and that there is nothing I can do short of complaining to Apple in the hopes of getting a replacement of a later revision. I was told by a "genius" at a different Apple store that my machine sounded about like he'd expect.
I'm getting a system board replacement tomorrow, but have been told not to expect it to make a significant difference. I figure I must do it before Apple would consider further action.
Any advice at all will be greatly appreciated. Sorry for the long message...
Thanks,
ctcaldwell
iMac G5 17" Mac OS X (10.4.5)

Mine is still fairly new as I picked it up off ebay a couple weeks ago brand new. So I don't know when it was actually manufactured. The part of the noise that gets under my skin is that soft but constant background whining coming from the CPU fan. It doesn't really sound like anything rubbing or a bad bearing, just the sound that an electric motor makes. But, it just seems to resonate from the lower left hand side where the air intake is.
So quite accidentally one day I held my hand under the left hand side and it completely muffled the whine sound. You could still here the hum and the sound of air but the irritating element was gone. Playing around a little more, I opted to tape a business card under that lower left hand corner, bridging the gap from front to back to still allow an airspace for the fan's suction. It knocks out about 90% of the whine.
It's been running that way for two weeks with no ill effects. Yes, the fan speeds up and slows down when needed. Normal at rest RPM is 1500 and mid to upper 50's on the temp. The highest temp I've seen under max continuous load is 65 with the fan at 4000 rpm.
I did experiment with something longer than the business card but I did then see a decrease in cooling capability. The isight models have their suction ducted out the back and I bet that gets rid of that resonance.
So all in all it still makes less fan noise than my old B&W, it's just that the B&W wasn't up on the desk so close to our heads. But, If your fans are constantly on high, there is a procedure for resetting something in power management, I just can't find it right now. Hope this helps.

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My iMac g5 starts up , responds slow, freezes after approx. 2 minutes, then upper fan starts running high and loud. ANy ideas on what could be wrong? Worth fixing?

My iMac g5 starts up , responds slow, freezes after approx. 2 minutes, then upper fan starts running high and loud. Any ideas on what could be wrong? Worth fixing?

Could be over-heating. Try cleaning out the air vents.

IMac G5 (w/iSight) running slow and hot on web browsers

Hello-
I've had my iMac for 4+ years and haven't any problems I couldn't fix on my own until now....
Machine is an iMac G5 w/ iSight with all original hardware except an extra 2GB of memory (for a total of 2.5). Over the last couple of months, my web browsers have begun to run slower and slower (mainly Safari, but I also use Firefox). Also the processor fan (I believe) comes on more quickly and frequently. It is now to the point that anytime there are any imbedded graphics, whether it's a youtube video, or a weather radar loop, or my kids are on webkinz, the fan kicks in and the top left corner gets extremely hot to the touch. As soon as I leave the page or close out the browser, the fan dies down. I cannot run any of these sites optimally. I am also getting quite a lot of page loading errors in Safari such as "Safari can't find the server." However, when I hit refresh the page comes right up. There does not seem to be a pattern to these messages. This only seems (so far) to be an issue with the browers. Today I simultaneously played a DVD, played songs on iTunes, and work in MS Word. No fan...
Here's what I've done so far:
Repaired disk permissions
Ran the extended hardware test (passed, no errors)
Ran diagnostics on my network connection (passed)
Reset Safari and Firefox incl. clearing the cache and deleting all cookies
Ran cleaning and maintenance w/ OnyX
Any thoughts or help would be much appreciated!
Thanks...
JD

Which Camino? Do you have the latest, which I think is 2.0.3? It's difficult to pinpoint why all your browsers might be slow to load.
You could try the Servers from OpenDNS which may be faster (and safer, since they are patched for DNS poisoning/redirects) than those of your ISP. Put these numbers in Network> DNS for the interface your are using, eg. Ethernet, Airport:
208.67.222.222
208.67.220.220
Then check to see if it's working by going to
http://www.opendns.com/welcome/
You can also test your speeds here
http://www.speedtest.net/
Here's something to read on slow browsers (in this case, Safari, but applicable to any browser.)
http://reviews.cnet.com/8301-13727_7-10354948-263.html
If the refresh option works quickly, that might indicate that your Internet speed is slow. Once you've been to a page, it's stored in the browser cache, so it doesn't need to reload everything from scratch. I don't notice any difference in speed from refresh loading, so I suppose my Internet speed, though only around 1MBPS, is fast enough not to have to depend on the cache.
I don't know for certain if that indicates a problem, but the CPU spiking temporarily to 100% on loading a page doesn't sound like a big problem. Your processor is by now relatively slow compared to newer machines and web pages are getting more complicated with more elements to load all the time.
Finally, those G5s do run kind of hot; it will only delay the arrival of the hottest temps, but putting a fan at the back does help a little. I use one even on this new iMac.
Message was edited by: WZZZ

Late 2010 iMac Running Sluggish and Loud-PLS HELP

I have only found one or two threads relating to my specific problem, and I still need more help. Anyone's help (...Linc Davis) would be very much appreciated.
First off, let me tell you what I am running.
Late 2010 model iMac (3.2 GHz intel core). OSX Snow Lion 10.6.8. 4GB Ram. 1TB hard drive (less than half full)
Here is where I have isolated the problem so far.
-Switching between applications is often very sluggish and laggy. It takes up to 10 seconds sometimes to open an appplication.
-Playing audio files with either itunes or preview. Quite often a song will stall for up to 5 or more seconds before playing again
-NOTE occasionally the audio actually cut out for five seconds and then start again later on in the song as opposed to simply stalling.
-Typing in search bars, this action is often sluggish and laggy as well.
-Clicking on icons and links. Example, at the start up window when I clicked on my user account it took about three seconds to bring up the username box
-Fan is working very loudly right from startup, and not slowing down at all.
Here are the solutions I have tried to no avail.
-Ran disk utility, everything came up as ok
-monitered my CPU usage with various problem causing applications. The RAM usage is fine and should be working great, I almost always have more than half freed up RAM
-I replaced the thermal cream around the hard drive because it was over heating a bunch and I also gave it a good clean. This fixed the over heating problem but the laggin still occurs.
-SMC reset (twice). no change.
I don't know what to do next, somebody please help. Do I have any malware? Is my harddrive failing?
p.s. I'm pretty noob to the intricacies of going deep into computers, but I can follow steps and figure out what's going on easy enough.

Hello, see how many of these you can answer...
See if the Disk is issuing any S.M.A.R.T errors in Disk Utility...
http://support.apple.com/kb/PH7029
Open Activity Monitor in Applications>Utilities, select All Processes & sort on CPU%, any indications there?
How much RAM & free space do you have also, click on the Memory & Disk Usage Tabs.
Open Console in Utilities & see if there are any clues or repeating messages when this happens.
In the Memory tab, are there a lot of Pageouts?

My new Imac 24", 2.8GHz Intel Core is suddenly making a loud fan noise

Please help!
This Imac is only a week old. I bought it on apple online store. This is 24" 2.8GHz Imac and it's been the best computer I've ever had. It was wonderful to work and silent until yesterday. And suddenly I can't stand the fan noise coming from my new Imac. I downloaded i-stat Pro to check the status of my computer and it reads *CPU fan:1198rpm, hard drive:1198rpm, optical drive: 4401rpm*
what is wrong with my computer?
I searched many mac forums, and I've tried many things including shutting it down and unplugging everything and replugging everything after a while, but nothing solves this problem. Does anybody have experienced this problem? I am not even using many applications. I am only using safari, and the fan is at full speed. SO LOUD! What can I do to solve this? Should I take it to apple to look at it?

Hello lovingimac
Welcome to Apple Discussions
That sounds like there is something wrong with the temp. sensor for the optical drive.
If carefully following the SMC reset instructions below, does not fix the fan issue:
http://docs.info.apple.com/article.html?artnum=303446-en
Then yes you need to make a trip to your local Apple service center.
Dennis

IMac G5 1.6GHz 17" screen w/ 512mb RAM and a fan problem

I do not know if anybody else has had this problem, but I have a fan problem, my computer is very loud, I have seen other computers that are the same as mine, I think I have a very loud fan and it goes all the time.

Hello Walter - I am glad your problem has been resolved. What was probably not stressed enough in the posts you read is that you have to have a retail version of any new OS you want to install. Failing that, you would have to get install discs for exactly the same model iMac you have.
Make sure, that when the Keene store installs Tiger for you, that they give you the install discs so you can boot from them if you have any other problems. You might also consider getting more memory, you are operating with the bare minimum. Don't buy it at the Apple store, order it on line from [macsales.com] or [newegg.com] or [smalldog.com] it's much less expensive and really easy to install. Make sure that whatever memory you do buy has a lifetime guarantee.
If I stand on a hill, I can see Mt Monadnock

IMac starts with sound but remains with Apple logo and the clock running indefinetely

After software upgrade ( from mavericks to new mavericks ) iMac doesn't start anymore. It remains always in the same mode: after the sound of start the Apple logo and the clock that runs indefinitely without the start of the software. Someone knows what to do?

Take each of these steps that you haven't already tried. Stop when the problem is resolved.
Step 1
The first step in dealing with a startup failure is to secure the data. If you want to preserve the contents of the startup drive, and you don't already have at least one current backup, you must try to back up now, before you do anything else. It may or may not be possible. If you don't care about the data that has changed since the last backup, you can skip this step.
There are several ways to back up a Mac that is unable to start. You need an external hard drive to hold the backup data.
a. Start up from the Recovery partition, or from a local Time Machine backup volume (option key at startup.) When the OS X Utilities screen appears, launch Disk Utility and follow the instructions in this support article, under “Instructions for backing up to an external hard disk via Disk Utility.”
b. If you have access to a working Mac, and both it and the non-working Mac have FireWire or Thunderbolt ports, start the non-working Mac in target disk mode. Use the working Mac to copy the data to another drive. This technique won't work with USB, Ethernet, Wi-Fi, or Bluetooth.
c. If the internal drive of the non-working Mac is user-replaceable, remove it and mount it in an external enclosure or drive dock. Use another Mac to copy the data.
Step 2
If the startup process stops at a blank gray screen with no Apple logo or spinning "daisy wheel," then the startup volume may be full. If you had previously seen warnings of low disk space, this is almost certainly the case. You might be able to start up in safe mode even though you can't start up normally. Otherwise, start up from an external drive, or else use either of the techniques in Steps 1b and 1c to mount the internal drive and delete some files. According to Apple documentation, you need at least 9 GB of available space on the startup volume (as shown in the Finder Info window) for normal operation.
Step 3
Sometimes a startup failure can be resolved by resetting the NVRAM.
Step 4
If you use a wireless keyboard, trackpad, or mouse, replace or recharge the batteries. The battery level shown in the Bluetooth menu item may not be accurate.
Step 5
If there's a built-in optical drive, a disc may be stuck in it. Follow these instructions to eject it.
Step 6
Press and hold the power button until the power shuts off. Disconnect all wired peripherals except those needed to start up, and remove all aftermarket expansion cards. Use a different keyboard and/or mouse, if those devices are wired. If you can start up now, one of the devices you disconnected, or a combination of them, is causing the problem. Finding out which one is a process of elimination.
Step 7
If you've started from an external storage device, make sure that the internal startup volume is selected in the Startup Disk pane of System Preferences.
Start up in safe mode. Note: If FileVault is enabled, or if a firmware password is set, or if the startup volume is a Fusion Drive or a software RAID, you can’t do this. Post for further instructions.
Safe mode is much slower to start and run than normal, and some things won’t work at all, including wireless networking on certain Macs.
The login screen appears even if you usually log in automatically. You must know the login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.
When you start up in safe mode, it's normal to see a dark gray progress bar on a light gray background. If the progress bar gets stuck for more than a few minutes, or if the system shuts down automatically while the progress bar is displayed, the startup volume is corrupt and the drive is probably malfunctioning. In that case, go to Step 10. If you ever have another problem with the drive, replace it immediately.
If you can start and log in in safe mode, empty the Trash, and then open the Finder Info window on the startup volume ("Macintosh HD," unless you gave it a different name.) Check that you have at least 9 GB of available space, as shown in the window. If you don't, copy as many files as necessary to another volume (not another folder on the same volume) and delete the originals. Deletion isn't complete until you empty the Trash again. Do this until the available space is more than 9 GB. Then restart as usual (i.e., not in safe mode.)
If the startup process hangs again, the problem is likely caused by a third-party system modification that you installed. Post for further instructions.
Step 8
Launch Disk Utility in Recovery mode (see Step 1.) Select the startup volume, then run Repair Disk. If any problems are found, repeat until clear. If Disk Utility reports that the volume can't be repaired, the drive has malfunctioned and should be replaced. You might choose to tolerate one such malfunction in the life of the drive. In that case, erase the volume and restore from a backup. If the same thing ever happens again, replace the drive immediately.
This is one of the rare situations in which you should also run Repair Permissions, ignoring the false warnings it may produce. Look for the line "Permissions repair complete" at the end of the output. Then restart as usual.
Step 9
Reinstall the OS. If the Mac was upgraded from an older version of OS X, you’ll need the Apple ID and password you used to upgrade.
Step 10
Do as in Step 9, but this time erase the startup volume in Disk Utility before installing. The system should automatically restart into the Setup Assistant. Follow the prompts to transfer the data from a Time Machine or other backup.
Step 11
This step applies only to models that have a logic-board ("PRAM") battery: all Mac Pro's and some others (not current models.) Both desktop and portable Macs used to have such a battery. The logic-board battery, if there is one, is separate from the main battery of a portable. A dead logic-board battery can cause a startup failure. Typically the failure will be preceded by loss of the settings for the startup disk and system clock. See the user manual for replacement instructions. You may have to take the machine to a service provider to have the battery replaced.
Step 12
If you get this far, you're probably dealing with a hardware fault. Make a "Genius" appointment at an Apple Store, or go to another authorized service provider.

IMac boots up fine - but getting clock, calculator, weather and can't proceed to desktop.

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Hi, Eustace---
Thanks for your suggestions, which didn't hurt, as you said!
Zappling the pram did not solve the problem - destop appears as normal upon startup, but clicking anywhere on screen produces four widgets. Clicking anywhere makes them disappear, reappear, disappear, and so on.
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Silly problem! But one that has kept me from using my iMac for 4 days now.
I think it is time for *sigh* a visit to the Apple store, and a few hundred dollars out the door. But hopefully not!
If you have any more suggestions, I'm open in the meantime.
Thanks AP

Imac (Intel based) fan runs continuously and loudly.

Have done a SMC reset, and the fan is still running loudly and continuously. Only 1 application open - firefox. This has been an ongoing, continuous problem.
Thanks in advance for any help you might offer.

Have had the same problem .. have reset the PRAM & SMC, doubled the amount of RAM. Fans runs & Activity Monitor shows most of RAM is used up with nothing open. Running Snow Leopard 10.6.8 on a Mac Book with 4g of RAM, Apple Support showed no hardware problems. ????

When I turn on my MacBook it just shuts down straight away however when I plug in the charger and turn it on it stays on but the screen stays black and the fan is the loud

Help

Try resetting the SMC and PRAM.
- Reset the PRAM: http://support.apple.com/kb/HT1379
- Reset the SMC: http://support.apple.com/kb/HT3964
Bob

My power mac G5 won't boot up but has red flashing light and intense fan noise.

I Have a Power Mac G5 that flashes a red light that I've never seen before. There is nothing on the monitor and the fan noise is incredible.
HAs anyone ever had this problem?

Hi Michael,
It's normal for the fans to go full speed if the OS won't load to handle them.
Where is this red light, on the logic board, or front panel?
Can you count the beeps or flashes?
1 beep = no RAM installed
2 beeps = incompatible RAM types
3 beeps = no good banks
4 beeps = no good boot images in the boot ROM (and/or bad sys config block)
5 beeps = processor is not usable
In addition to the beeps, on some computers the power LED will flash a corresponding number of times plus one. The LED will repeat the sequence after approximately a 5-second pause. The tones are only played once.
Note: In this case, a flash is considered to be 1/4 second or 250 ms or greater in length.
http://support.apple.com/kb/HT1547
LED 1—CPU A: red—contact Apple or an Apple Authorized Service Provider
LED 2—Overtemp: red—contact Apple or an Apple Authorized Service Provider
LED 3—Power On: red—the main power is on
LED 4—Trickle: yellow—Power Mac G5 is plugged into the wall correctly
LED 5—Open Firmware good: green—no problem
LED 6—CPU B: red—contact Apple or an Apple Authorized Service Provider
LED 7—Checkstop: red—contact Apple or an Apple Authorized Service Provider

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I have been having audio issues with the imac 27. plugging headphones or speakers causes cpu to run crazy, the mic in the triband trrs jack does not work, and the imac runs hot, and will not go into power saver mode.
When I came in I found my nephew who was listening to some music on the imac, and I felt the back top of the imac and it was hot as ****. I almost burned my hand. I realized then that he had plugged his headphones in.
Unplugging the headphones or speakers can solve some of these problems.
But, this is not an acceptable fix.
Please contact Apple and urge them to fix these sound card issues.
If anyone does not have these problems in w7 with the imac 27 even after the latest bootcamp and imac updates, let us know right here. I think this affects every one of the late 2009 imacs and maybe some earlier ones too running windows 7.
Here's the post I recently ran on the headphone jack issue.
Not only does the cpu run crazy but the imac 27 gets very, very hot. Since I unplugged the headphones, it runs much, much cooler.
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Also, we certainly want a stereo mix option for audio in or out, or what is called "what you hear" or wave out. Imac is supposed to be much geared to multimedia apps.
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Mac has a great reputation. I hope they remedy these problems right away.
Anyone whose imac 27 or 24 whose headset plug is working correctly. Let us know! I don't think anyone's is, but I think that few people understand that their cpu is running so much faster with the plug in, plus few even understand the combo jack and the triband, or trrs audio jack! Out of 4 audio technicians I talked to, not one of them knew what a trrs jack was or that you even have a mic in jack as part of the headset jack!
When I told one senior that it worked on the Mac side, he didn't believe for a while, thought my sound might be recorded from the onboard mic, but I proved it to him by tapping iaudibly on my iphone mic headset and and it showing up in garage band clearly and listening to big difference in audio.
As for a usb audio adapter, I am in a neon light environment and find that those adapters are more sensitive to electrical interference. Besides I want to use the headset jack as it was meant to be used!
Thats it.
Again, if anyone using an imac 27 and windows 7 64 or 32 doesnt have these problems, let us know! We are all anxious for a fix!
Best to all!

Yes, I have been dealing with this problem since early January. I just can't believe that apple would not have the necessary driver for the sound card in the Imac 27! That's like trying to run a race and not bothering to tie your shoes! How can they not have something as basic as the sound connections working???
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As you can see I am quite angry about this, and getting more angry with each day Apple ignores every imac purchaser who expected to use Windows on the machine! Is the software for a sound card driver that difficult?
Having a computer which doesn't have sound that works correctly, is like having a car without seat, you can still drive it but isn't very **** comfortable.

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Before I saw Mike Sombrio's post:
I restarted the IMac without unplugging the power cord, but the noise was still there when the IMac came back on. Then I repeated this about 10 minutes later, (restarting the computer without unplugging the power cord). This time the noise was no longer there. I don't know what's going on. I hope this problem does not return. Any explanations? Is this a sign that my IMac is having serious problems? Any advice?

IMac 27" (Late 2012) Loud Fan and Overheating Issues, causing Hard Drive Failure

Hi all,
I'm having some serious overheating issues with my new iMac. Any help to help me solve this problem would be gladly appreciated since it's really beginning to bug me. Here's what's has happened:
I noticed in the first few hours of switching the iMac on that there was a short burst of very loud fan noise. This has been happening about once every two days since and every time I haven't been doing any heavy processing with the system. I've noticed that the main fan will spin, on average, at 1200rpm. Is that normal? The iMac is very well ventilated and sits right next to a window...
I have also boot camped the iMac with a copy of Windows 8 so I could run some fairly power-hungry games. I intentionally purchased a high end iMac (27" display, Intel Core i7 3.4GHz, Nvidia GeForce 680MX Graphics, 1TB Fusion drive) and expected the iMac to run games flawlessly. However, after a few days, I noticed that the CPU and GPU had shot up to a worrying 80°C whenever I ran power-hungry games, with a very loud hissing noise from the fan. After running games for about 10 minutes, the fan will stop hissing, causing the GPU and CPU to increase to 100°C. The iMac then fails and switches off unexpectedly without any warning. After analysing the Windows event logs, I received an event ID 41: The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly.
As this occurred about six times whilst I was testing my iMac's performance, I think my hard drive has now begun to fail - sometimes I will hear the hard drive make a click noise, about once every 5 seconds. Sometimes, the clicking noise causes OS X and Windows to run very slowly (even though minimal RAM is being used and nothing too intensive (Safari, Mail etc.) is being processed). Running Repair Disk and Repair Disk Permissions under OS X's recovery mode as well as a repair in chkdsk in Windows suggests that there were no problems with the hard drive. All I can do is wait a while for the clicking noise to stop, and then performance will increase. I have backed up everything externally.
I have also performed a reset of the SMC as well as the PRAM, which hasn't really helped.
Any help will be appreciated. I will gladly provide any extra logs etc. if they're needed.
Thanks so much,
Alex.

Alex Cummaudo wrote:
I've noticed that the main fan will spin, on average, at 1200rpm. Is that normal? The iMac is very well ventilated and sits right next to a window...
That's the default fan speed on iMacs, so there isn't any problem with this.
Alex Cummaudo wrote:
I have also boot camped the iMac with a copy of Windows 8 so I could run some fairly power-hungry games. I intentionally purchased a high end iMac (27" display, Intel Core i7 3.4GHz, Nvidia GeForce 680MX Graphics, 1TB Fusion drive) and expected the iMac to run games flawlessly. However, after a few days, I noticed that the CPU and GPU had shot up to a worrying 80°C whenever I ran power-hungry games, with a very loud hissing noise from the fan. After running games for about 10 minutes, the fan will stop hissing, causing the GPU and CPU to increase to 100°C. The iMac then fails and switches off unexpectedly without any warning. After analysing the Windows event logs, I received an event ID 41: The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly.
You must know that Boot Camp isn't compatible with Windows 8 and that Apple hasn't released drivers for Windows 8, so it can fail. Install Windows 7 inmediately until Apple launches updated drivers.
As it looks like the hard disk is damaged, I would take the Mac to an Apple Store. It's in warranty, so it should be repaired for free or you should receive a new one

IMac running hot

Our IMac is running very hot and the fans are running loudly and constantly. To fit it into a smaller space I took the stand off it. Where are the vents on these machines and what can I do to improve airflow without the stand attached?

The air intakes are located across the bottom of the iMac. If you are blocking the intakes by setting the iMac down off the stand, then you are just moments away from a total meld down.
The iMac's do not do well in tight spaces, you would do better putting the stand back on and finding a more open space or getting a new desk.

17" iMac G5 2GHz (ALS but no iSight) runs hot and LOUD fans

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