Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Halcyon

macrumors 6502
Original poster
Sep 21, 2006
335
0
I just noticed a very low, almost imperceptible (but loud enough to make itself be known it's there), clicking noise on my new 20" alum iMac (for more specs read my sig). It is a constant noise that will not change in intensity (it is on all the time, starts as soon as I turn on the machine, stays on all the time and will not get any louder or quieter, until I shut down the machine).

All this makes me think it must not be the HD, unless it's spinning all the time...which I seriously doubt. Maybe it's the fan, but that will mean the fan is stuck and working full time, never stopping. In which case, how can I tell when the fan is on? Unless the fan is on all the time on both of my iMac's, I can't seriously hear when they go on and off...as they probably should according to CPU temp (then again, how can you tell what the temp is?...I've read some posts in which they state the exact working temp???).

I hope this is not a serious problem, because even though I can take my computer in to be replaced or fixed with the authorized dealer (remember it is still under warranty), it does take weeks to get it back...I replaced the mighty mouse on my 17" iMac and it took 3 weeks!!!

TIA for any help/guidance.
 
I just noticed a very low, almost imperceptible (but loud enough to make itself be known it's there), clicking noise on my new 20" alum iMac (for more specs read my sig). It is a constant noise that will not change in intensity (it is on all the time, starts as soon as I turn on the machine, stays on all the time and will not get any louder or quieter, until I shut down the machine).

All this makes me think it must not be the HD, unless it's spinning all the time...which I seriously doubt. Maybe it's the fan, but that will mean the fan is stuck and working full time, never stopping. In which case, how can I tell when the fan is on? Unless the fan is on all the time on both of my iMac's, I can't seriously hear when they go on and off...as they probably should according to CPU temp (then again, how can you tell what the temp is?...I've read some posts in which they state the exact working temp???).

I hope this is not a serious problem, because even though I can take my computer in to be replaced or fixed with the authorized dealer (remember it is still under warranty), it does take weeks to get it back...I replaced the mighty mouse on my 17" iMac and it took 3 weeks!!!

TIA for any help/guidance.

To possibly help determine if it is the HD, in the Energy Saver pane of System Preferences, select "Put the hard disks to sleep when possible". This may help narrow down if it is indeed your HD if it quits after a little bit of inactivity on the computer.
 
Hard disk spin continuously while the computer is on, as do fans. Those are the items it could be. There are 3 fans and 1 hard disk, along with your optical drive.. which wouldn't spin unless a disc is inserted.

My guess is a fan has a wire that it keeps touching against as it spins, making a clicking noise. Since fans speed up and slow down with use, if the clicking does not change pace at all I'm going to guess it's hard disk related.
 
OK. According to your suggestions I set up the HD to sleep whenever possible and put the the computer to sleep...and the clicking stops. So, unless the fans also stop when the computer goes to sleep, it has to be the HD.

Now, the big questions is, I'm I in trouble with this HD? Can this very low clicking noise be considered "acceptable" or should I run and have it replaced before total failure happens?

TIA

BTW - I found the widget that gives you temps and fan rpm's...what are the normal operating temps and fan speeds for iMac's? Is this info available somewhere?
 
i had the same problem...turned out it was a wire that was touching one of the fans, as was suggested previously. very annoying problem, but easily fixed. hopefully thats all it is with your comp.
 
i had the same problem...turned out it was a wire that was touching one of the fans, as was suggested previously. very annoying problem, but easily fixed. hopefully thats all it is with your comp.

Being that it's still under warranty, if it means opening up the computer I'll have to send it to the dealer. I'm backing up all my data at the end of every day in case the HD fails...which seems to be the problem as the noise is a steady one, as opposed as if it was the fans it would change when the fans kick in (unless, like said before, my fans are stuck on full throttle and don't spin down).

Will see how this thing develops and if the noise gets any worse I'll have to take it in for repairs.

On a different subject - Now that I got the iStat widget, where can I find info on what the normal operating temps should be? (just to check and see if my unit is within the norms).
 
Update

can you share with us why it took you 3 weeks to replace your mighty mouse?

Sorry for responding so late, but holidays and some time off came first :)

Right now I'm stationed in a third world country in South America and that's about the time it takes for the local Apple dealer to process the claim with Apple USA and have them ship another one and for it to clear customs.

On the bright side (hope so) I had my machine turned off for almost two weeks and now that I've turned it on the clicking sound is almost imperceptible. It has not gotten any louder or worst in the two days it's been on, so who knows, it might never come back or it can get worst at any time...
 
Sorry for responding so late, but holidays and some time off came first :)

Right now I'm stationed in a third world country in South America and that's about the time it takes for the local Apple dealer to process the claim with Apple USA and have them ship another one and for it to clear customs.

On the bright side (hope so) I had my machine turned off for almost two weeks and now that I've turned it on the clicking sound is almost imperceptible. It has not gotten any louder or worst in the two days it's been on, so who knows, it might never come back or it can get worst at any time...

If you're still trying to determine whether it is a HDD or your fans that are clicking you could download SMCFanControl and try to raise the speed of the fans slightly in order to see if the rate of clicking changes.
 
If you're still trying to determine whether it is a HDD or your fans that are clicking you could download SMCFanControl and try to raise the speed of the fans slightly in order to see if the rate of clicking changes.

Smc is a very good program, and just for the record, my CPU fan is spinning at 1197-1200rpm, HD fan spinning at 1335rpm, optical drive spinning at 699rpm, if the fan is hitting a wire, i bet you its the thermometer that keeps the temp of the 3 main components excluding the video card. Tell us what you get:).
 
I just downloaded SMCFanControl, will play with it and post my findings...just give me a couple of days.

TIA
 
Apple says take it in

I have a two-month-old iMac 20" -- one of the early 2008 models...2.66 g with 2 gs of ram.

Was quiet as anything until a couple weeks ago, started hearing a clicking sound. Steady, just like Halcyon described. If I lean close to the Mac, I can actually hear something vibrating. I hoped it would go away. It has not, so I contacted Apple today. Tried SMC, no luck. It sounds to me like one of the cooling fans.

Anywa, so Apple says take it in. Problem is the nearest Apple store is 2.5 hours away. So tomorrow, I'll see what they say when I drive to get it serviced.

Yuk -- not too happy about this.

I just noticed a very low, almost imperceptible (but loud enough to make itself be known it's there), clicking noise on my new 20" alum iMac (for more specs read my sig). It is a constant noise that will not change in intensity (it is on all the time, starts as soon as I turn on the machine, stays on all the time and will not get any louder or quieter, until I shut down the machine).

All this makes me think it must not be the HD, unless it's spinning all the time...which I seriously doubt. Maybe it's the fan, but that will mean the fan is stuck and working full time, never stopping. In which case, how can I tell when the fan is on? Unless the fan is on all the time on both of my iMac's, I can't seriously hear when they go on and off...as they probably should according to CPU temp (then again, how can you tell what the temp is?...I've read some posts in which they state the exact working temp???).

I hope this is not a serious problem, because even though I can take my computer in to be replaced or fixed with the authorized dealer (remember it is still under warranty), it does take weeks to get it back...I replaced the mighty mouse on my 17" iMac and it took 3 weeks!!!

TIA for any help/guidance.
 
I just noticed a very low, almost imperceptible (but loud enough to make itself be known it's there), clicking noise on my new 20" alum iMac (for more specs read my sig). It is a constant noise that will not change in intensity (it is on all the time, starts as soon as I turn on the machine, stays on all the time and will not get any louder or quieter, until I shut down the machine).

All this makes me think it must not be the HD, unless it's spinning all the time...which I seriously doubt. Maybe it's the fan, but that will mean the fan is stuck and working full time, never stopping. In which case, how can I tell when the fan is on? Unless the fan is on all the time on both of my iMac's, I can't seriously hear when they go on and off...as they probably should according to CPU temp (then again, how can you tell what the temp is?...I've read some posts in which they state the exact working temp???).

I hope this is not a serious problem, because even though I can take my computer in to be replaced or fixed with the authorized dealer (remember it is still under warranty), it does take weeks to get it back...I replaced the mighty mouse on my 17" iMac and it took 3 weeks!!!

TIA for any help/guidance.

3 Weeks to just exchange a Mighty Mouse. They could have just sent it to Apple and gave you a new one. Cheep place they weren't willing to do that.. :/

Hugh

Never mind I didn't see that you are not a in a place where getting these things easily. I would think they would have more then one on hand though. :/
 
Fast clicking noise from bottom of iMac

I have the same problem that several have described--noise from the bottom (not really left or right, but then, it's rather loud, so who knows which side it's actually coming from). I've installed the smcFanControl, and the only adjustment that seems to change the noise is increasing the CPU fan speed. The tapping seems to grow a little more steady in increasing the CPU fan speed, but no adjustment makes it stop. Does this offer any additional insight for anyone who might be able to help solve the issue?
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.