Throttling in New i9 MacBook Pros Appears to be Due to Power Delivery Chip

A user posting on reddit and in the MacRumors forums has given a detailed account of their findings and attempts to circumvent the throttling previously discovered on the new MacBook Pro 15" models featuring the six-core i9 Intel CPUs.

The user goes on to explain that one of the internal power limits set for the device may not be appropriate for the power draw of the CPU and identical to previous MacBook Pro models, causing the power delivery chip (known as a voltage regulation module, or VRM) to report an over power condition that forces the clock of the CPU down to scale back power. This sets up the same conditions to allow throttling to occur once again.

These conditions may be presenting themselves due to the new six-core design of the i9 CPU featured here. While Intel increased the core count of the CPU, they did not increase the thermal design power (TDP), or the amount of dissipated power manufacturers should plan to have to cool for a proper CPU design. This is an issue because this number usually reflects normal usage, and does not account for turbo modes. It's also likely it can exceed the draw of previous four core CPUs given the similarity of clock speeds and process nodes they are featured on.

A method for tuning this limit is provided in the post, but it requires executing a command manually or via script each time the computer boots, and would likely void the warranty if Apple technicians discovered it. Still, the user posts results of benchmarks showing successive runs with no throttling. Manufacturers will always quote likely reduced component lifetimes if used outside of their specifications, but the results appear stable, and there is no thermal throttling of the CPU, the original suspected cause of this issue.

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.

As for whether this issue is related to the hardware design of the MacBook Pro, that is possible as well. While iFixit's complete teardown of the current 15-inch MacBook Pro is not yet available, the previous teardown reveals significant differences in the VRM chips that power the GPU and CPU of the device.

macbook pro gpu vrms

GPU power components

The GPU power components seen above are on the top side of the logic board near the GPU die, and thermal grease can be seen on the components, indicating that they interface with the heatsink in the device. This is in contrast to the same components for the CPU, which are featured on the rear side of the logic board with no thermal interface to the top of the package, as seen below.

macbook pro cpu vrms

CPU power components

Additionally, the publicly available data sheets for these parts indicate more differences that suggest their thermal profiles will be different. The International Rectifier part for the GPU features a lower thermal resistance, meaning it can better dissipate its heat to the surrounding areas (board, air, heatsink) than the Intersil part for the CPU. Additionally, it boasts a higher power efficiency, meaning it dissipates less power itself to deliver the same amount of power as the Intersil part.

Along with the heatsink path provided for the IR parts, it's clear they will not be capable of driving the same amount of load in any sustained mode. This makes sense given GPUs can see high loads for longer periods, but this could be an area of improvement for future MacBook Pro models from Apple, especially since it has typically chosen GPUs with very similar thermal design power limits (TDPs) to the CPUs in its MacBook Pro line.

Related Roundup: MacBook Pro
Tag: Intel
Buyer's Guide: MacBook Pro (Neutral)
Related Forum: MacBook Pro

Popular Stories

iPhone 17 Pro in Hand Feature Lowgo

iPhone 17 Pro to Reverse iPhone X Design Decision

Monday July 7, 2025 9:46 am PDT by
Since the iPhone X in 2017, all of Apple's highest-end iPhone models have featured either stainless steel or titanium frames, but it has now been rumored that this design decision will be coming to an end with the iPhone 17 Pro models later this year. In a post on Chinese social media platform Weibo today, the account Instant Digital said that the iPhone 17 Pro models will have an aluminum...
iOS 26 Feature

Everything New in iOS 26 Beta 3

Monday July 7, 2025 1:20 pm PDT by
Apple is continuing to refine and update iOS 26, and beta three features smaller changes than we saw in beta 2, plus further tweaks to the Liquid Glass design. Apple is gearing up for the next phase of beta testing, and the company has promised that a public beta is set to come out in July. Transparency In some apps like Apple Music, Podcasts, and the App Store, Apple has toned down the...
imac video apple feature

Apple Launching These 15+ Products Later This Year

Sunday July 6, 2025 8:05 am PDT by
The calendar has turned to July, meaning that 2025 is now more than half over. And while the summer months are often quiet for Apple, the company still has more than a dozen products coming later this year, according to rumors. Below, we have outlined at least 15 new Apple products that are expected to launch later this year, along with key rumored features for each. iPhone 17 Series iPho...
iphone 16 pro models 1

Here's How the iPhone 17 Pro Max Will Compare to the iPhone 17 Pro

Saturday July 5, 2025 1:00 pm PDT by
Apple should unveil the iPhone 17 series in September, and there might be one bigger difference between the Pro and Pro Max models this year. As always, the Pro Max model will be larger than the Pro model:iPhone 17 Pro: 6.3-inch display iPhone 17 Pro Max: 6.9-inch displayGiven the Pro Max is physically larger than the Pro, it has more internal space, allowing for a larger battery and...
iPhone Car Key Kia

Here's Which Vehicles Offer iPhone Car Keys

Sunday July 6, 2025 3:03 pm PDT by
In 2020, Apple added a digital car key feature to its Wallet app, allowing users to lock, unlock, and start a compatible vehicle with an iPhone or Apple Watch. The feature is currently offered by select automakers, including Audi, BMW, Hyundai, Kia, Genesis, Mercedes-Benz, Volvo, and a handful of others, and it is set to expand further. Apple has a web page with a list of vehicle models that ...
apple wallet drivers license feature iPhone 15 pro

Apple Says iPhone Driver's Licenses Will Expand to These 8 U.S. States

Tuesday July 8, 2025 11:26 am PDT by
In select U.S. states, residents can add their driver's license or state ID to the Wallet app on the iPhone and Apple Watch, providing a convenient and contactless way to display proof of identity or age at select airports and businesses, and in select apps. Unfortunately, this feature continues to roll out very slowly since it was announced in 2021, with only nine U.S. states, Puerto Rico,...
iphone 17 pro render majin bu

New iPhone 17 Pro Renders Highlight Apple Logo and MagSafe Design Changes

Sunday July 6, 2025 8:43 pm PDT by
New renders today provide the best look yet relocated Apple logo and redesigned MagSafe magnet array of the iPhone 17 Pro and iPhone 17 Pro Max. Image via Majin Bu. Several of the design changes coming to the iPhone 17 Pro model have been rumored for some time, such as the elongated camera bump that spans the full width of the device, with the LiDAR Scanner and flash moving to the right side. ...
apple account card feature

Apple Account Card Expanding to More Countries

Tuesday July 8, 2025 7:34 pm PDT by
Apple is expanding the ability to add an Apple Account Card to the Wallet app to more countries, according to backend Apple Pay changes. With iOS 15.5, Apple updated the Wallet app to allow users to add an Apple Account Card, which displays the Apple credit balance associated with an Apple ID. If you receive an Apple gift card, for example, it is added to an Apple Account that is also...
iPhone 17 Pro in Hand Feature Lowgo

iPhone 17 Pro Coming Soon With These 14 New Features

Friday July 4, 2025 1:05 pm PDT by
Apple's next-generation iPhone 17 Pro and iPhone 17 Pro Max are just over two months away, and there are plenty of rumors about the devices. Below, we recap key changes rumored for the iPhone 17 Pro models. Latest Rumors These rumors surfaced in June and July:Apple logo repositioned: Apple's logo may have a lower position on the back of the iPhone 17 Pro models, compared to previous...

Top Rated Comments

johnalan Avatar
91 months ago
Sounds like an Intel issue. Just another reason for Apple to drop them and begin using their own chips. Intel certainly isn't helping themselves here.
It's not an Intel issue.
Score: 35 Votes (Like | Disagree)
IPPlanMan Avatar
91 months ago
Apple either knew and it said “**** it, ship it.”

Or it didn’t know because it didn’t adequately performance test it.

All Apple had to do was run this test to see the issue.

Apple isn’t even trying anymore. They know we’ll buy it anyway.
Score: 25 Votes (Like | Disagree)
LavenderCaptain Avatar
91 months ago
I don't understand how anyone could think this is anyone but Apple's fault... Intel sells the same chips to everyone - in volumes that make sales to Apple look like a rounding error. If there was a problem with the chips, that would be the story because EVERYONE would be screaming. Intel share prices would take a beating, etc.

Even if Apple made their own chips, the same thing could happen. This comes from somebody either not bothering to test, or the tests not being aligned to actual use... Or maybe the test unit being different from what was actually manufactured at the factory in China, in which case it's a quality control failure.

Nobody buys an i9 to just surf the web and leave it idle most of the time.
Score: 23 Votes (Like | Disagree)
Winter Charm Avatar
91 months ago
It's fun to pretend to be an Electrical Engineer :)
Measurements clearly show this fixes the problem. ¯\_(ツ)_/¯.

Maybe you're just in denial. Apple ****ed up hard.
Score: 22 Votes (Like | Disagree)
Audigy Avatar
91 months ago
I feel this is more Intel's fault. Apple is caught in the middle(...)
You feel wrong. Who designed the board without complying with the correct specifications needed for that processor, using a voltage regulator design that is clearly insufficient for it, thus overheating? Apple.
Score: 18 Votes (Like | Disagree)
pankajdoharey Avatar
91 months ago
This is very sad, Apple is so focused on iPhones, they have forgotten the power users who actually make content and Apps for iPhones, Macs and iPads.
Score: 18 Votes (Like | Disagree)