One thing to keep in mind is that power delivery is currently probably the most criticised part of most main boards from just about any main board designer. It's even hard to remember a handful that actually got praised for their power delivery, I'm quite sure none of them were laptops, and all of them were really high end enthusiast desktop parts that are way out of scope for what Apple is doing with the MBP. Just something to keep in mind.
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Throttling in New i9 MacBook Pros Appears to be Due to Power Delivery Chip
- Thread starter MacRumors
- Start date
- Sort by reaction score
Thanks for the info. Do you feel this is something that can be fixed via a firmware fix?
“They’ll fix it”.... is that the new standard for Apple now?
[doublepost=1532447697][/doublepost]
Spot on. Exactly right.
yes, I was being very simplistic.
for anyone else who wants more reading information on what TDP actually is:
https://en.wikipedia.org/wiki/Thermal_design_power
Its not about thermal limits, its about power limits. Give these CPUs a strong power supply and no limits, and they will attempt to boost as high as they can. MSI estimates that the new i9 CPU can draw around 150 Watts of power, which is totally a ridiculous amount for a laptop. If we were to require that all laptops can dissipate this kind of heat, we'd be back to the era of 4kg laptops.
Intel's CPUs are configurable (in software) to how much power they will try to draw. Laptop manufacturers usually set this to the CPU's TDP when BIOS (or whatever they are using these days) is first run. The TDP for these CPUs is 45Watt, so setting the limit to 45W means "you can maximally draw 45W over prolonged periods of time". The laptop could maybe cool more, say, 50W, but the CPU is not allowed to go that far.
Now, it seems that Apple chose a different path instead, setting this power limit to a very high 100W. The idea is not to restrict the CPU in any way but the thermals — allowing it to get as fast as the circumstances (in this case, cooling system) allows. This is why CPUs in Apple laptops traditionally run hot under load — since they get the absolute max that the chassis can handle. And its also why Apple sometimes appeared to have better CPU performance than other laptops using same CPUs. Why 100W? Because its a very high limit and CPUs Apple was using until now in laptops didn't get close to consuming this much. Its just a "very high number" for the purpose of not restricting the CPU at all.
This spectacularly fails however in case of the new Coffee Lake chips. Because of increased number of cores and increased turbo frequencies, they can potentially draw much more power (essentially becoming desktop class CPUs). So when Apple tells them "hey guys, you can use 100W for as long as you want" they go "don't mind if I do", which puts massive stress on the power delivery system which can't handle these kind of loads for more then a couple of seconds. As a result, the power components overheat and send an emergency throttle signal to the CPU.
Bottomline: yes, these CPUs can perform better with better cooling. But then its the same as sticking a desktop CPU into a laptop. The problem with MBP throttling is not inadequate cooling (the MBP can easily maintain a 6 core CPU at 3.2Ghz frequencies per core as shown by multiple users) but rather misconfigured CPU power limits.
^^ This!! My sentiments exactly! Seems like Apple is too afraid to make a thicker laptop. So much for Tim Cook's stance on diversity.
I blame the Universe for forcing a set of thermodynamic laws on us that prevents us from having the ultra thin laptops we all have a right to.
It is something that can be mitigated with a firmware change. There is still a very limited set of data, so we don’t know how conservative Apple’s settings truly are.
I mean... the point is that nobody can say exactly what it is because it's a marketing term that gets manipulated by manufacturers as they please. As such it's mostly meaningless, and Apple engineers obviously know this. I can't believe that they base their logic board and cooling designs on TDP. Frankly, I would find it hard to believe that they base it on anything other than their own testing in their own labs.
I find it difficult to believe that they didn't know about this throttling issue, and because of how they've handled their other hardware problems in the past, I have a difficult time believing any of the excuses that they may have.
Whats concerning to me is the lack of thermal interface on the CPU power components. Power components get hot, thats why most PC motherboards put heat sinks on the power delivery system. Without adequate cooling, even if you can coax the power delivery system to give out more juice, its going to get hot and I would expect it to drastically shorten the lifespan of the parts.
It will be interesting to see what the failure rate for the logic boards will be as time goes on.
I dont see myself spending $3000+ on a laptop that the battery can last only 3 years, the keyboard cannot withstand the mobile environment, and the OS is at the lowerest quality level as it has been! Now you buy a top configuration mac that cannot event perform due to the design issue??
I have already stopped using ipad mini and switched to Samsung S2. after a little bit of time to get used to, now I cannot be happier that i switched. So apple does not want to upgrade the mini, I walked away. no biggy.
Now come to the laptop, i checked out the dell xps and windows 10. i was suprised how much they have improved over the past few years. Now if I can save 30-40% of the $$ and get some thing as 90% as good, why not? Especially macOS is getting buggier and buggier and the hardware is only "good" for 3-4 years anyway.
Very soon it will come down to the iphone!!!
It is very sad that Apple under current leadership believes people would just buy Apply. I think they missed one important thing here. For a eco system so close to itself, it has to be superior compare to other competitors. Steve Jobs made apple success was because he made everything near perfect. once it is not near perfect, why would people buy it with the hassle it is so closed.
Try to lose more telanted mac users and see how IOS apps can still keep going.
I have already stopped using ipad mini and switched to Samsung S2. after a little bit of time to get used to, now I cannot be happier that i switched. So apple does not want to upgrade the mini, I walked away. no biggy.
Now come to the laptop, i checked out the dell xps and windows 10. i was suprised how much they have improved over the past few years. Now if I can save 30-40% of the $$ and get some thing as 90% as good, why not? Especially macOS is getting buggier and buggier and the hardware is only "good" for 3-4 years anyway.
Very soon it will come down to the iphone!!!
It is very sad that Apple under current leadership believes people would just buy Apply. I think they missed one important thing here. For a eco system so close to itself, it has to be superior compare to other competitors. Steve Jobs made apple success was because he made everything near perfect. once it is not near perfect, why would people buy it with the hassle it is so closed.
Try to lose more telanted mac users and see how IOS apps can still keep going.
And the Dell with the issue, the review says just pop the case and spread new thermal paste, of course this definitely violates your warranty.
https://www.ultrabookreview.com/14875-fix-throttling-xps-15/
https://www.ultrabookreview.com/14875-fix-throttling-xps-15/
Great points. But the main issue is having something throttled so much that it almost never can reach it's full advertised potential in normal, expected working conditions. They will take your money for the advertised speed but won't deliver said speed.
I'm sure you can solder new VRMs on to the MBP too, no problem at all. Or desolder the i9 and bring back the quad core from last year's model
The one and only question that I have is if and when Apple is going to publicly acknowledge this?
They'll probably acknowledge it sometime in 2020 after a new model comes out and the class action lawsuits start to pile up.
Proof of throttling:
"And it’s here you can see the reason Razer used the 35W configuration for the CPU: there is simply no more thermal headroom when gaming. Had the CPU been allowed to run at 45W, the cooler would have either been overwhelmed thermally, or it’d have to crank up even louder from an already loud state. Rather than throttle down the GPU, Razer decided to hit the CPU and while throttling neither is obviously ideal, tuning down the CPU makes more sense than tuning down the GPU."
https://www.techspot.com/review/1664-razer-blade-2018/page3.html
"And it’s here you can see the reason Razer used the 35W configuration for the CPU: there is simply no more thermal headroom when gaming. Had the CPU been allowed to run at 45W, the cooler would have either been overwhelmed thermally, or it’d have to crank up even louder from an already loud state. Rather than throttle down the GPU, Razer decided to hit the CPU and while throttling neither is obviously ideal, tuning down the CPU makes more sense than tuning down the GPU."
https://www.techspot.com/review/1664-razer-blade-2018/page3.html
God I hated that show even before this MEME famous moment. Total american rubbish.
Better check razerrumors.com, I bet they also have outrage threads like this one.
"This fix will not address total system power draw becoming excessive, such as long sustained loads from the CPU and GPU, but it is possible Apple could issue a fix similar to the one outlined in the reddit post that is stable. "
Fix is a strong word - it's reducing the max power state, and time spent in that state. The VRMs are underspecced for the job in the end, and I wonder what running them to their limits will do for board life.
It looks like there certainly is improvements to be made, and those will reduce load on the VRMs, but the i9 should have been paired with higher rated ones.
Fix is a strong word - it's reducing the max power state, and time spent in that state. The VRMs are underspecced for the job in the end, and I wonder what running them to their limits will do for board life.
It looks like there certainly is improvements to be made, and those will reduce load on the VRMs, but the i9 should have been paired with higher rated ones.