Temperatures on 13 and 15 models compared

[semistandard]

People who have experience with both.
Is it true that temps on 13 model are noticeably lower than 15 inch when idling / doing non-intensive tasks? (Anecdotal experience from a few sources - 13 inch surface tamps are few degrees cooler than 15 inch...).
And when stressing the CPU - is there any difference between the two?
The folklore is that both can hit near 100C under load...

And how are the temps (when not stressing the GPU) on 13 inch model of this years are compared to 15 inch of 2016/2017? I understand that their cooling systems are similar and both have same number of cores...

 

[dhhamilton]

People who have experience with both.
Is it true that temps on 13 model are noticeably lower than 15 inch when idling / doing non-intensive tasks? (Anecdotal experience from a few sources - 13 inch surface tamps are few degrees cooler than 15 inch...).
And when stressing the CPU - is there any difference between the two?
The folklore is that both can hit near 100C under load...

And how are the temps (when not stressing the GPU) on 13 inch model of this years are compared to 15 inch of 2016/2017? I understand that their cooling systems are similar and both have same number of cores...

[doublepost=1536260298][/doublepost]I have a i7 13" that approached the 100C mark and was uncomfortable to use - I broke it down and removed the OEM and applied the coat of thermal paste - knocked about 10-12 degrees off it - better, but still warmer than my 15" or MBAir

 

[frou]

Does the 2018 15" ever switch over to the Intel integrated graphics, or is the Radeon active and producing heat at all times?

 

[semistandard]

Does the 2018 15" ever switch over to the Intel integrated graphics, or is the Radeon active and producing heat at all times?

It does when not connected to external monitor. If you want, you can even disable the dGPU (again, when not connected to the external monitor).

[doublepost=1536260298][/doublepost]I have a i7 13" that approached the 100C mark and was uncomfortable to use - I broke it down and removed the OEM and applied the coat of thermal paste - knocked about 10-12 degrees off it - better, but still warmer than my 15" or MBAir

What 15'' model do you have? Also 2018? Or an earlier one?

 

[justinf77]

I've been using my 15" for light work all day and it's perfectly cool to the touch. No issues here. Of course this changes when I push the machine but I never really have any problem with temps being too high.

 

[jerryk]

Does the 2018 15" ever switch over to the Intel integrated graphics, or is the Radeon active and producing heat at all times?

By default it will only use the dGPU when needed (external monitor, graphics calls in applications, etc.). You can control this by enabling/disabling graphics switching. And if you want to go deeper you can set parameters to prevent the DGPU frombeing used.

 

[Gamer-Dad]

Having owned both 2018 models, the 13” i5/512/8 and my current 15” 2.6/512/16/560x, at idle, the 13” runs a few degrees cooler (about 40C). The 15” sits about 43C. Under load, both machines hit around 93-98C. Remember the 15” is pushing 2 additional cores as well as 4 additional hyper threaded cores, faster DDR2400 memory as well, along with the deification CPU when needed (the 13” integrated graphics is higher end than the integrated 15” graphics).

 

[semistandard]

****. May be I should add additional 300$ and get that 15 model after all.
Any advantages for 13 inch model except the small factor?

 

[matthewadams]

It's true.
My 13" work laptop sits around 39C (with 2 monitors attached!), without the monitors roughly the same but the fans occasionally completely switch off.
My 15" is about 10C warmer overall (admittedly im mostly using it with 1 screen attached). Right now cruising at 47C in idle.

They both hit near 100C when under load (that's just how the CPUs work) - do you make your decision based on temperatures alone? That doesn't make a lot of sense.

 

[semistandard]

It's true.
My 13" work laptop sits around 39C (with 2 monitors attached!), without the monitors roughly the same but the fans occasionally completely switch off.
My 15" is about 10C warmer overall (admittedly im mostly using it with 1 screen attached). Right now cruising at 47C in idle.

They both hit near 100C when under load (that's just how the CPUs work) - do you make your decision based on temperatures alone? That doesn't make a lot of sense.

Of course not on the temps alone. There are other factors - price for example is not the last one and i5/512/16 model is cheaper than 15 inch with 512 SSD upgrade by something like 300$ (plus I get a USB hub with for whatever it's worth).
Portability is important - I've already got big and heavy laptop that can run most of graphic intensive tasks (unity/blender/playing games here and there) , so I don't really need dGPU that much. 6 cores are nice, however as it seems for some reason i5-8259u seems to match (at least according to some benchmarks) i7-7700hq in power which is more than enough for anything I do at the moment, so it seems that the 13 model has got enough CPU power... And while 13 model lacks dGPU, let's admit that - the a dGPU on 15 model is a crappy one - and if I need anything really intensive, I doubt that the 555x or even 560x will save the day.
While 15 screen is undoubtedly nicer, the 13 inch screen should suffice for most of things I plan to use it for. If there's something that needs a big screen - I doubt that going from 13 to 15 will make that much of a difference. After all, their sizes are comparable.

Common sense tells not to bother with 15 and just get the 13 inch model. (Cheapier, lighter = less back pain, and powerful enough).
However, 15 inch model is much more shiny... So I am afraid that I can regret my choice in a few months from now.

 

[matthewadams]

I switched from a 15" to a 13" at work mainly because of portability. As someone who's rushing from meeting to meeting with a laptop in my hands, it's quite a difference.

For your use-case I also doubt there'd be any significant difference other than size.
I'm personally really happy with the 13" for work (it easily beats the 15" 2015 i had before anyway).
Even connecting two monitors (one of them 4k) doesn't make the machine slower in any way (which couldnt be said about the 2015 15")

 

[happyslayer]

I've been using my 2018 15" sitting here in a Starbucks for the last hour doing web, email, and Quickbooks stuff and my machine is currently at 37 deg C (per iStat Menus). When I push it playing games or doing massive software installs it will definitely get warm/hot. Gaming is too hot and I use a lap desk - between 90 & 95 C. But general use it stays pretty cool.

 

[airlied]

****. May be I should add additional 300$ and get that 15 model after all.
Any advantages for 13 inch model except the small factor?

better battery?

 

[Gamer-Dad]

better battery?

Better battery life on 15”

 

[airlied]

Better battery life on 15”

so......no advantage except smaller factor (and cheaper)?.......

 

[Gamer-Dad]

Depends on what you want and what works for you. Check prices at B&H They are having a really nice sale until 9/8. You can score the base 15" for $2099 or the 2.6 15" for $2499, no tax if outside New York. The base i5 13" TB model is $1599 and the i5 with 512GB SSD is $1899. You could also get your local Best Buy to price match there prices, but you'll pay tax but have a better return policy. I was fortunate to be close to Delaware so I was able to get the B&H price at Best Buy and have no tax. $2499 for the mid 15" is a steal especially with no tax

 

[iMacDragon]

And if you want to go deeper you can set parameters to prevent the DGPU frombeing used.

Please enlighten? I've been trying to figure out how to temporarily disable dgpu when on battery since gfxcardswitcher basically no longer works!