21 inch vs 27 regarding heat

onthecouchagain

macrumors 604
Original poster
Mar 29, 2011
7,382
1
Is there a difference, small or significant, in how the two models handle or dissipate heat? In other words, just cause the 27 inch is larger, presumably, there's more room/space inside? Does this allow more air flow, better venting, as oppose to the smaller 21 inch? Using this line of thought, the 21 would therefore be more crammed together and have less airflow?

Or is there like zero difference?

I ask because I was using a 27 inch at work today for a special job, and running videos on it all day, basically, and it felt like the back never got very hot.
 

SR20DETDOG

macrumors regular
Jan 25, 2011
186
0
Queensland Australia
All Macs will get hot under load.
That doesn't really answer the question though.

I don't think the difference would be particularly great. While the 21.5" iMac is more compact and cramped it also uses a lower wattage CPU and less powerful GPU. There is a thread around here somewhere where members posted up their temps while under load for both the 21.5" and 27" iMacs which would answer your question but I can't seem to find it.
 

onthecouchagain

macrumors 604
Original poster
Mar 29, 2011
7,382
1
Maybe best having a look at teardowns on ifixit.

That'll show you physically whether there is any real difference.
I actually did, and it looks like there's very little difference. Checking the measurements, in terms of height and length, the 27 is only about 5 inches longer, and 3 inches higher. I guess that doesn't allow for that much extra room, which is why I came and posted the question.

Thanks for the replies. If anybody knows more, please chime in.
 

derbothaus

macrumors 601
Jul 17, 2010
4,060
4
Most likely a wash. The faster upgrades for each form factor will be slightly hotter. So hard to tell because of all the Intel CPU throttling as well. Depends on what you do. But they should list an idle temp at least.