MacBook Pro 2015 Retina 13inch Performance Limit by Apple?

[nMeCri]

Hi,

 

I am pretty new here, because of some strange performance issues of my Mac I decided to write here asking for some help. I already posted this on Apple Community but it seems no-one saw my post.   i want to have a try here.

 

The CPU on my MacBook Pro 12,1 (i5-5257U) would only use up to 18 Watts of power and the system total power usage is well below 35 Watts with a 60 Watt PSU connected and CPU Core temperature under 85 Degrees C (fan speed 80%) while running Cinebench R23. Therefore I believe there is something limiting the CPU performance. 

As I didn't recorded the CPU power draw before, and I noticed this issue recently, I wonder if Apple is lowering the CPU performance of older Macs?

An early review article on Internet (https://www.notebookcheck.net/Apple-MacBook-Pro-Retina-13-Early-2015-Notebook-Review.139621.0.html) even said that the CPU is limited to 32 Watts, which is higher than the Intel rate.

 

This performance drop occurred back to the time I upgraded my OS from High Sierra to Mojave. Sometime it is really frustrating because I can't use the full potential of my Mac. It could even get laggy if I play Netflix or Prime-Video on full screen.

Firstly I thought it was the Mojave System which could be not well optimized or something like that so I upgraded to Big Sur, but nothing changed.

 

Recently because of the lagging and throttle issues I get my System back to High Sierra, with a clean install (format the SSD and co.), I still experiencing the issues as I described before.

Boot-Rom of my MBP is 426.0.0.0.0, SMC Firmware is 2.28f7.

I ran Apple Diagnostics, nothing found.

I reset SMC, PRAM and NVRAM. I also disconnected the battery and power from the MBP for about 30 min, to reset any possible chips.

I cleaned the internal and reapplied thermal paste (MX-4) of the CPU, didn't help.

I have upgraded my SSD from the original 128G one from Apple to a WD SN550 using adapters, runs well and R/W speed normal.

The battery in this MBP was replaced by Apple in Winter 2019 which is in pretty good shape, coconutBattery shows 99% battery health.

The CPU gets about 1820 points in Cinebench R23, the CPU temperature during that marking, stays at, as described before, around 80 Degrees C with fan speed at about 4k RPM (full speed is 6.2k RPM), so the temperature is definitely ok and well below the limit which could lead to thermal throttle. The power draw of the whole system, include full brightness screen, is around 35 Watts.

The frequency of the CPU often reach 3GHz with only about 8 Watts power consumed. Pretty weird.

The frequency of the Iris GPU stays low always, no matter if I will watch a Movie, YouTube or anything, the frequency of the GPU won't go above 600 MHz, most of the time it stays at 400MHz.

I also discovered that the Mac doesn't have any performance differences if the AC is disconnected. (same power draw and same Cinebench Score with battery). It seems that the power supply does nothing than charge the battery and the Mac still uses power from the battery although it is connected to AC.

Could that be a faulty or failing Power Supply which caused those issues? Or internal cable connections?

Or it is on software Level? .kext or SpeedStep?

Or is Apple using firmware updates to limit performance of older Macs?

 

I did what I could trying to fix my Mac, it should not run that slow even it is 6 years old. I maintained the machine pretty well with cleaning every 6 Months. It is my first laptop I bought with my own money back in 2015, and it is my only laptop too. 

Is there any possibility that I could fix it?

 

Greetings

Chipei

 

[Computerfreak_213]

This may or may not be the answer to your problem
 

 

This also happened on my iPhone because of a new update. For example, apple release a update on the M1 MacBooks that used the drive as virtual ram. The update almost burned the hard drive’s life. Apple sometimes does make big mistakes in updates.

 

 

[ki8aras]

cpus have whats called a tdp, meaning a max power draw under sustained loads,if you go on intel's website you can see the max power draw of your cpu,regardless of what charger you plug into it

besides that the i5-5257U is a dual core cpu, meaning that it would slow down at some point or another given that today's programs require a higher amount of cores to function properly

 

you also mentioned that the slowdown occured after a system update,so maybe apple implemented some change in the new os that required more cpu time,thus slowing your pc down? (the only way to see if the updated os is the cause of your issues is to revert back to an older version and see if your system responsiveness increases)

 

final note: apple has been known to tweak their laptop cpus power profiles so i wouldnt find it surprising if they tweaked their max tdp to 18w

[nMeCri]

29 minutes ago, ki8aras said:

cpus have whats called a tdp, meaning a max power draw under sustained loads,if you go on intel's website you can see the max power draw of your cpu,regardless of what charger you plug into it

besides that the i5-5257U is a dual core cpu, meaning that it would slow down at some point or another given that today's programs require a higher amount of cores to function properly

 

you also mentioned that the slowdown occured after a system update,so maybe apple implemented some change in the new os that required more cpu time,thus slowing your pc down? (the only way to see if the updated os is the cause of your issues is to revert back to an older version and see if your system responsiveness increases)

 

final note: apple has been known to tweak their laptop cpus power profiles so i wouldnt find it surprising if they tweaked their max tdp to 18w

I checked the Intel page about this CPU and it shows the TDP is 28 Watts and adjustable to 23 Watts, still, it's far more than what I can get with my 5257U. Also, the review article I mentioned in my post above, under Energy Management - Power Consumption, the author had up to 32 Watts of CPU power consumption and up to 63 Watts of system total power consumption. So I don't think Apple tweaked the TDP, at least not when this machine came out in 2015.

So I think, maybe, Apple adjusted the TDP with their Firmware Updates for older Macs. 

[nMeCri]

50 minutes ago, Computerfreak_213 said:

This may or may not be the answer to your problem
 

 

This also happened on my iPhone because of a new update. For example, apple release a update on the M1 MacBooks that used the drive as virtual ram. The update almost burned the hard drive’s life. Apple sometimes does make big mistakes in updates.

 

 

Yeah, I also heard about the stuff about M1 Macs that having extreme high hard drive read and write volume. 

It is already obvious that Apple would change device characteristics using software updates to lower performance of older machines. 

[ki8aras]

34 minutes ago, nMeCri said:

I checked the Intel page about this CPU and it shows the TDP is 28 Watts and adjustable to 23 Watts, still, it's far more than what I can get with my 5257U. Also, the review article I mentioned in my post above, under Energy Management - Power Consumption, the author had up to 32 Watts of CPU power consumption and up to 63 Watts of system total power consumption. So I don't think Apple tweaked the TDP, at least not when this machine came out in 2015.

So I think, maybe, Apple adjusted the TDP with their Firmware Updates for older Macs. 

im pretty sure they wouldnt try something like that, especially after the iphone slowdown fiasco (but i could be wrong)

[nMeCri]

36 minutes ago, ki8aras said:

im pretty sure they wouldnt try something like that, especially after the iphone slowdown fiasco (but i could be wrong)

That's also what I think, Apple won't hit that wall again and mess up with this after iPhone affair. So I am considering Power Supply failure or charging board failure or software issue... But can't get clear.