Fan noise when screensaver active (iMac Retina 5K)

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Fan noise when screensaver active (iMac Retina 5K)

Hello & thanks for your time to reading my question.

I'm using a iMac Retina 5K, 27-inch, Late 2014 with a AMD Radeon R9 M295X graphics card with 4 GB VRAM, actually with OS X 10.11 El Capitan, but the problem exists still OS X 10.10 Yosemite.

When screensaver is active (all variants of picture-change-screensavers), the cooling fans are turning up and the mac gets noisy.

At first I assumed higher CPU-load and checked the activity monitor, but the CPU load seems to be not the problem (1-2% load when screensaver is active). I try a Reset of SMC and NVRAM, but no results. I've try the screensavers with another pictures (also Apple-standard) and try a different user account - with the same fan-noise result.

Finally I think, the picture-screensaver are producing a lot of GPU load - but why and how I can resolve this? Have you similar experiences with noisy fans when picture screensaver is active on the 5k iMac?

Thank you for your help!

With best regards

Arndt

iMac (Retina 5K, 27-inch, Late 2014), OS X El Capitan (10.11)

Posted on Oct 5, 2015 2:58 PM

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Answer 1

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rkaufmann87

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Oct 9, 2015 11:12 AM in response to ArndtB

Try resetting the SMC 2-3 times back to back. Sometime the reset does not work the first or second time.

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Answer 2

ArndtB Author

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Oct 9, 2015 11:20 AM in response to rkaufmann87

I'm sorry for my late response, I was busy in the last days. Thank you for the hint to repeat the SMC-reset, it was helpful. I've try it, but this not resolved the issue for me. 😟

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Answer 3

Oct 9, 2015 1:50 PM in response to ArndtB

Hello, I might have a similar issue with my late 2012 27" iMac. The fan becomes extremely noisy even if I just turn on the computer after some time. I have seen no connection to the screensaver, however. I have noticed that in the Task manager the "kernel_task" process is taking up to 700% of the CPU, even with no particular apps running in the background.

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Answer 4

tom44

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Nov 5, 2015 4:40 AM in response to marcopico

I'm also having the same issue with a brand new late 2015 imac (3.2ghz M390). I even returned the first one that I was sent, but a second imac is still making the same ticking noise at 1200rpm (idle). Having lived with it for a couple of weeks on two different machines in a not particularly quiet neighbourhood I am pretty sure that this is a problem and that apple can't have intended these imacs to sound like this at idle (compare to a late 2013 imac that is essentially silent at idle bar a bit of airflow).

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