Powered Cooler & Throttling

Queen6

macrumors G3
Original poster
All those who own the Retina MacBook are well aware of the "sprint" nature of Core M, and subsequent throttling under sustained heavy loads, which for some precludes any form of "heavy lifting "

My own 1.2 holds 1.9GHz - 2GHz with all Core`s lit up holding at around 8W plus, then it will drop off to 1.3GHz, surging back to 2GHz, thermal throttling is in effect. Now place the Notebook on a small powered cooler, turn it on, and you can watch (Intel Power Gadget) the MacBook recover from the throttling event. The 1.2 MacBook will now hold 2GHz, as long a the cooler is running...

Not entirely practical on the go, however if you do need to push the Retina MacBook, this does appear a method to hold the higher frequencies.

Fully charged on mains supply;
  • Ambient 26C (78.8F)
  • CPU total load 99.9%
  • CPU Temp 92.2C (197.96F) @ 2.00GHz

Have doubts, give it a try :) biggest impact I have ever observed with a Mac when using powered cooler :apple:

Q-6
 
Last edited:

Queen6

macrumors G3
Original poster
It is illustrated pretty clearly on this other new thread with a video pf the guy setting the MB in a tray of water giving the same results.

Pretty neat!
True, equally impractical. The powered elevator I tired is a third of the MacBooks footprint and drops the temps significantly, allowing the CPU to turbo boost without restraint.

Q-6
 

MyopicPaideia

macrumors 68020
Mar 19, 2011
2,010
790
Sweden
No no, of course, not implying that what the video shows is a practical way to do it, just saying it illustrates that a little cooling goes a loooooong way with the core M, which is pretty neat.
 

jimboutilier

macrumors 6502a
Nov 10, 2008
647
42
Denver
One of the first things I tried when getting my 1.3ghz rMB was testing its heat throttling characteristics and the impacts of a few cooling pads I had purchased or cobbled together over the years.

In normal 20C room temperature, under max load the CPU would quickly jump to 94C (from about 42C at idle), then throttle to remain below 95C. You noticed the performance drop (maybe 20%?) but it wasn't horrible. And as soon as the load went away the temps would drop and throttling would be suspended once temps got back to normal for a bit.

With a normal "granule filled" cooling pad, temps rose slightly slower and throttling was slightly lower, but nothing significant. A gel pad or fan pad worked better and throttling was reduced significantly but still occurred for me.

A true cooling pad (air flow or gel pad contact at a constant 5C) completely eliminated throttling and CPUs never got past about 80C. But its not really practical for portable or travel use. The dual core M is still no powerhouse but it was an interesting experiment that points to better performance in cooler environments and worse performance in hotter environments.
 

airattack111

macrumors member
Dec 9, 2008
82
3
Does anyone make a cooling pad for the rMB? It would seem like you would have to put thermal paste on the aluminum to get any cooling affect haha.

I'm getting a clear skin for this and will probably cut out the skin where the motherboard is so it can still get natural air cooling without having a big sticker over the aluminum.
 

Queen6

macrumors G3
Original poster
The powered cooler I have is ancient, equally it`s quiet and approximately a third of the size of the rMB. All you need is air flow across the base of the Unibody.

Adding a skin should not make a big difference, equally it`s a adding a thermal barrier, recommend you try "before and after" or leave the base plate bare. From my own observations with Core M small things add up, and I also get a "kick" out of doing more with less...

Q-6
 

keviig

macrumors 6502
Jun 7, 2012
498
225
Even something as simple as a USB fan at the back of the machine is enough to keep mine from throttling. Just having some airflow under the unibody seems to be enough.
 

Theozz

macrumors member
Jun 4, 2015
51
20
The powered cooler I have is ancient, equally it`s quiet and approximately a third of the size of the rMB. All you need is air flow across the base of the Unibody.

Adding a skin should not make a big difference, equally it`s a adding a thermal barrier, recommend you try "before and after" or leave the base plate bare. From my own observations with Core M small things add up, and I also get a "kick" out of doing more with less...

Q-6
What powered cooler do you use? I'm curious ;)
 
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