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knuk114 · Nov 11, 2005, 12:35 AM

Long story, but I bought an iMac G5 Rev B about a week before Apple announced the new 2.1 gHz version. Needless to say, I elected to return the old machine for the new one, paying about $35 for the upgrade after restocking fees, returning the MM, etc.

Well, my "old" machine was pretty nice - it was dead quiet and ran cool. The new machine, which I picked up last weekend, is great - the only beef I have is that it definitely runs hotter, (right now the CPU temp is 140F and GPU 126) and it is not quiet. In fact, as the CPU heats up, I can hear the fan noise increase in frequency and the top vent area, top part of the screen gets pretty warm.

From all of you who have the new iMac, is this typical? I kind of hate to raise a stink about it, but I do find it a little annoying.

Beyond that, it is a definite improvement - the sound is better, graphics smoother, screen better.

brokenjago · Nov 11, 2005, 01:46 AM

Do you have anything that could be blocking the vents, or the free flow of air to the vents? This would probably make the fans run more quickly. When do the fans speed up? Simply during normal operation, or when you're doing CPU intensive stuff, such as editing Video or huge images?

d0ubled0wn · Nov 11, 2005, 07:29 PM

I've not heard the fan speed increase at all on my 20" Rev C, even playing graphics intensive games. It's disappointing to hear that some users still experience this problem even after 3 revs.

hostage · Nov 20, 2005, 08:13 AM

I´m having the same problem with the new iMac.

I´m worried that having the computer shipped to iceland could have hurt the fan...

if i put my fingers over the fan intake the noise stops.. ?

where can i get the info for the cpu heat ? and also can i control the Fan speed ?

rgds

derekd · Nov 20, 2005, 09:12 AM

I've just got my 20" isight imac, and FWIW it's virtually silent apart from the disk. Only once did I hear a fan: when it didn't wake properly from sleep, and crashed. I've installed Hardware Monitor 3.1 and it shows

CPU 56C, GPU 55C, HD 47C, NB 73C, ODD 41C

I'm not sure what ODD & NB are, or what are normal values are here ;-)

Reagrds, Derek

dazzla · Nov 20, 2005, 12:40 PM

CPU 58C, GPU 57C, HD 46C, NB 75C, ODD 45C

I can hear my fan, cover the circle outlet and it's silent. I'm sat in a silent room though, and these keystrokes are louder than the fan.

No Time 4 Love Dr. Jones · Nov 20, 2005, 01:32 PM

Coming from building my own PCs with "advanced" cooling solutions, the iMac fan noise is a Godsend. The amount of acceptable noise is always subjective, though.

volcano · Nov 20, 2005, 01:37 PM

Originally Posted by No Time 4 Love Dr. Jones

The amount of acceptable noise is always subjective, though.

Especially when your entire computer is at eye-level in front of your face.

I haven't had any noise issues with my Rev. B iMac, but I'm sad to see these type of issues still arising after a 2nd revision.

Will C · Nov 20, 2005, 02:17 PM

Originally Posted by derekd

I'm not sure what ODD & NB are, or what are normal values are here ;-)

Reagrds, Derek

ODD - perhaps optical disc/disk drive?

mduell · Nov 20, 2005, 04:44 PM

Originally Posted by derekd

I've just got my 20" isight imac, and FWIW it's virtually silent apart from the disk. Only once did I hear a fan: when it didn't wake properly from sleep, and crashed. I've installed Hardware Monitor 3.1 and it shows

CPU 56C, GPU 55C, HD 47C, NB 73C, ODD 41C

I'm not sure what ODD & NB are, or what are normal values are here ;-)

Northbridge (chipset) and optical disk drive are my best guesses (and consistent with the temps shown).

m4rtin · Nov 23, 2005, 03:48 PM

Originally Posted by derekd

it's virtually silent apart from the disk.

I had assumed it would be absolutely quiet, is that naïve?
I can't hear the fan but there is a low, yet constant, noise from the disk (I assume).

Can anyone confirm this is normal? I just got it yesterday and I'm paranoid something might be wrong...

dejablue · Nov 25, 2005, 09:26 AM

i've had my new imac for about 2 weeks now and can hear nothing but the fan. although not loud it is the typical "ticking" fan noise. if i put my had over the rear fan hole it goes away. i guess the real question is....should the imac be as quiet as a notebook?, or is some noise to be expected?

Fonzie · Nov 25, 2005, 11:58 AM

You haven't heard fan noise until you've heard my iMac rev.a when I play any game or import music from a cd. Now while doing a bit of surfing a listening to music the fans are not at all silent or quiet. I have to turn up the music to a higher level to not hear the fans, but instead I have really loud music which isn't any better.

I understand that there has to be some noise from the fans but then again i don't.

volcano · Nov 26, 2005, 10:38 PM

Martin and Dejablue - your noise levels are normal. The G5 is a hot, powerful processor - you cannot expect it to be as quiet as an iBook or Powerbook. And like I stated earlier, the iMac is different because your entire computer is right in front of your face, instead of on the floor or near the ground like a typical tower. In any event, it's a powerful machine - and you cannot expect it to be completely silent. That's unrealistic. It contains a plethora of mechnancial parts, and they get hot.

Unless your iMac sounds like a jet plane about to take off, you shouldn't worry about it.