Not sure how that works! I have always wondered that. I know the surface tablet has fans, not sure how an iPad keeps cool.
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MacBook Misconceptions about Heat, throttling, and cooling
- Thread starter romesk90
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Not sure how that works! I have always wondered that. I know the surface tablet has fans, not sure how an iPad keeps cool.
You would have to monitor ASD with those apps to figure out if it's throttling or not. All you need is Intel Power Gadget. CPU Core Clock, Temps, and Power draw is all you need to figure out if it's throttling or not.
You cannot do that. ASD is all pre built. All the tech does is run it. It runs on its own, outside of OSX (sort of). It has its own system it runs on.
Edit: I may have misunderstood. If I get what you are saying, you mean run intel power gadget while ASD is running? I am not sure if ASD allows for that but I'll check with apple
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I believe you are right.. They may block running apps outside of the test suite. I just tried it and couldn't get Power Gadget to run. I assumed it was possible but shame on me for not trying. Thanks for the catch.
It's not strange at all, because of the variables between the two versions. The OS X/Windows version runs on x86 code and uses a notebook/desktop class GPU, depending on system. The iOS version runs on ARM code, and is using a mobile GPU. Two completely different systems, code bases, and hardware platforms at play. Your rMBP warming up is to be expected when running a game - it will do the same thing with WoW, Diablo III, and Starcraft too (I'm still not in HoTS alpha/beta, but I'd assume the same applies there). The iPad is a completely different platform, with different power requirements, thermal envelopes, and cooling setups, so you honestly can't directly compare the two, even running the same game.
Well but one can still wonder why a graphically completely undemanding game like Hearthstone pushes the rMBP over the edge, while the iPad can also run it without problems, using probably just 10% of the energy.
Comparing with WoW or Diablo 3 is not really appropriate since those are graphically more demanding and can not (yet) be played on iPads. Is the x86 platform so much less efficient? Or are PC programmers just too lazy to program resource friendly? Blizzard was actually nice enough to include a frame rate limit in Diablo 3, which helps with noise and heat.
I was comparing WoW and Diablo III to Hearthstone on PC/Mac, not to iPad. One HUGE reason those games aren't on iPad is because their respective game designs really need the keyboard/mouse combo. I've seen people try to play WoW on a PC with touchscreen, it really doesn't work very well. But going back to your original question, you're comparing two completely different sets of code, on completely different (and incompatible) hardware. The assets (graphics, backgrounds) will be the same, but the underlying code is completely different.
I understand that the code and the platform is different. Yet in the end the information displayed on screen is identical - so I think it is fair to ask why it takes more power on the PC. Is it like flash vs. html5 videos - i.e. the engine on the PC side is inefficient? Or is it the overhead of running the OS on the side? I'm just being curious.
The thing is that you can't directly compare the two. Like I said in my earlier post, while the assets (graphics) are the same, the underlying code for rendering/placing them and the game itself are completely different. An x86 system is more powerful and complex than an ARM-based system (although that gap is closing quickly), so there are calls and functions on the PC/Mac side that don't have direct equivalents on iOS. In automotive terms, it's like comparing a gas engine to a diesel. Both types of engines will power the vehicle to your destination, but they way they work to achieve that is significantly different. The Flash vs HTML5 comparison may be the closest in terms of relevance to this case, but it's relatively simplified in comparison to x86 vs ARM. ARM is a much more efficient platform because of its use in handhelds and mobile devices, where battery life is at an even bigger premium than in laptops, but that comes at the cost of more complex computations that the x86 platform has.
And yes, the OS will play a role in whether the fans kick in on a Mac or Windows based machine. Based on my experience, Hearthstone will kick the fans into high gear on a Windows machine, and even to a larger degree than it does on my Mac.
Update on ASD:
You can run terminal in ASD so we ran a burn in test using the yes > /dev/null method.
The CPU PECI read as high as 101 celcius. So, the ASD test definitely are conservative (highest they read was 70-75).
The only thing I cannot see is, ASD does not seem to report DTS temperatures.
In either case, There does seem to be a bit of discrepancy between ASD temps and say iStat temps. Hard to compare the two as they are in different environments.
You can run terminal in ASD so we ran a burn in test using the yes > /dev/null method.
The CPU PECI read as high as 101 celcius. So, the ASD test definitely are conservative (highest they read was 70-75).
The only thing I cannot see is, ASD does not seem to report DTS temperatures.
In either case, There does seem to be a bit of discrepancy between ASD temps and say iStat temps. Hard to compare the two as they are in different environments.
you're right. Also one thing that may make it easier to explain. When rendering textures and sounds and such on an iPad or iPhone; they are rendering at sometimes 1/4 or even more the resolution than the games on PC. I don't mean physical resolution I'm talking texture resolution, big difference. They use lots of smoothing techniques to make it look better as well as using that high PPI to small screen size ratio to hide things and make it look better. Kind of like taking a picture on your iPhone and thinking "damn that is crystal clear" then uploading it to your computer and it doesn't look that good at all anymore.. lol
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I tried it on my Macbook and it shows different temps as well..I can't tell for sure if it's throtling. I could also plug in my wall meter and guess based on load and idle draws if the CPU is reaching full turbo. Again, that is a horrible method haha
while at the apple store the genius's showed me some interesting software.
A couple being thermtrip, hot, stress-o-matic, cpuBurn (these are Apples test on ASD)
All of which get the computer easily going to 101 Celsius
ASD only reports 2.9ghz for my machine while running. Not sure if this is a limitation in display or not, or if turbo boost is actually not kicking in under ASD. I would think turbo boost would be enabled under ASD, but I cannot tell and the Genius bar was not sure.
All of this testing is pretty exciting. I feel an intricate bond with my machine having a better understanding of everything. I still want more. I am growing hungrier lol.
If only the source code was available for these test i could know for certain what they are doing and the limits. I looked around, seems it is all closed source stuff : ( Oh well.
What attitude? Running a test where neither the Genius dude nor you understand the results is a waste of time....and pretty irresponsible of the Genius TBH, I doubt whether Apple would endorse that.
If you look at it that way, then yes you are correct.
However, I was vague. What I meant was, if you/the genius bar cannot fully explain something then you do not have much choice but to take matters into your own hands, which is what I am doing.
I am looking through the macbook plans by engineers, code, and alternative testing. I am learning lots and probably have a better understanding now (with lots more to learn) than most of the genius bar people at my local shop lol.
Did you know my macbook pro is most "efficient" at around 1200-1400 mhz? Had no clue. You can also set limits to your CPU (which most are probably aware). Some would see this as counter productive as you buy a machine capable of say 2.9ghz but you only utilize 2ghz. Through most of my testing, the machine runs more stable and cooler if you lower it.
Interesting, measured how? Doing what work/load? Computationally or power consumption?
Measured by apples code and settings. I am not sure how they came to the conclusion but it seems to me to be a balance of power (ghz) vs. energy (volts). It depends on what you are doing if it is worth it. Due to the way apples cooling is designed, sometimes you getting the same or similar performance by lowering the CPU power. For example, when I play Diablo 3 my FPS with the same settings is identical if i run from 2.9ghz-3.4ghz so I limit to 2.9ghz and I run cooler as a result.
I have not fully tested this as I only recently found the piece in apples code. I have played with some of the settings and minor changes don't seem to affect performance but they do affect the heat. I might make a toggle switch app that allows you to change it easily, kind of like on windows how you have your "Power Saver", "Balanced", and "High Performance" setting.
Hmmm. Efficiency is a measure of output vs input, "code" and "settings" are just inputs.
Power consumption efficiency is always of interest in laptops as it governs battery life per charge but on the whole my primary interest is to get the work done in the time allowed and thereafter use the least battery. Under such varying conditions I find vanilla Mavericks does a good job unaided by unnecessary tinkering.
Power consumption efficiency is always of interest in laptops as it governs battery life per charge but on the whole my primary interest is to get the work done in the time allowed and thereafter use the least battery. Under such varying conditions I find vanilla Mavericks does a good job unaided by unnecessary tinkering.
As you lower the clock you are also lowering the amount of power it can consume. It is more efficient to run at a slower clock speed as your CPU will stay in more higher c-states which equals lower power consumption. 1200-1400MHz is great if you are sitting at the desktop but browsing the web or playing a game can be quite laggy at that clock speed. All that does depend on the game though, a game like Diablo might not be as affected but something like BF4 or Bioshock could become a little laggy at 1.2ghz.
This is why I rarely use my Macbook, it's really only good for short burst of performance and then throttling ensues.
What you are seeing are the consequences of using small heatsinks, small fans, conservative fan curves and an aluminum body. Aluminium tends to want to hold onto heat (or any temp for that matter) a little longer than plastic.
It could also be a problem of OSX not disabling the dGPU after you closed diablo. This would cause the temps to be higher because Apple made the design decision to have both CPU and dGPU on the same heatsink. This causes a heatsink to not be used in the way they were designed. The thermal paste Apple uses also is applied in an ample amount causing heat to be trapped in the pockets that form when the heatsink is pressed onto the chip. This can cause heat build up that can't be carried away by the heatsink. As shown below.. All manufactures are guilty of this...
Heat should be carried away from one end of the heat pipe to the other. When there are 2 different heat sources being carried away to different sections of the pipe it can cause the entire pipe to constantly be transferring heat to the cooling running chip and not to the fan. Heat will also want to get trapped in the location shown below..
This is an 11 inch laptop with a 45 watt quad core and a GT 650m. This is one way you can use 1 fan and combine heatinks the correct way. One side is the "hot" side and the other is the "cool" side. This means 1 fan can cool both without throttling and won't heat up the other chip if it's not in use.
This shows how a heat pipe works. Imagine two different heat sources trying to be cooled.. it isn't ideal IMO They probably did this ( in conjunction with not giving the mac a big enough power supply) because they didn't foresee a user putting a max load on both GPU and CPU in a gaming scenario. In their defense, they don't market a Mac as a gaming machine and it's not built to be one at all.
I don't claim to be an expert but after studying heat sinks and modding heatsinks in laptops and desktops this design is frowned upon. There are also other issues with Apple's design such as the thickness and length of the pipe which can also lead to heat issues. I rate a heat sinks' ability to cool a component based on how long the "cool down" time is. That is; the time is takes to drop a temp from a fully loaded chip back down to idle temps after letting the computer get up to idle temp. For example.. My G46VW has a fully loaded CPU temp of 83c, once the load has disappeared, it takes 23 seconds for the temp to drop to 38-40c which is my idle temp. My Macbook takes over 2 minutes and the fan is still screaming after 30 seconds from when the full load has disappeared. This is not an official test but it's my way of testing.
If I am wrong please state your facts because I love to learn.. one other thing, there is a reason Apple advertises CPU speed of their notebooks with the non turbo clock speed more often than the turbo boost speed.
This is a great post.
[doublepost=1490668217][/doublepost]I use throttlestop for my PC laptops is there something similar for macbooks. There is a lot of tolerance and I'm able to undervolt my pc laptops by a great margin and reduce temps by as much as 10c