Core i9 CPU slowdown in the new MacBook Pro tied to power regulation

A recent benchmark showed Intel’s Core i9-8950HK processor installed in Apple’s latest 15-inch MacBook Pro severely throttled in performance presumably due to cooling issues. After all, the MacBook Pro is extremely thin and the six-core chip needs sufficient cooling to reach its peak performance. But one Redditor claims that the throttling has nothing to do with processor heat, but rather the module that deals with regulating voltage provided to Intel’s CPU.

Called the voltage regulator module, this component is mounted on a PC’s motherboard and ensures that the processor is getting the correct amount of voltage. This component is required to support multiple processors with different levels of power requirements. Thus, if you swap out a processor using a new chip with a different power requirement, the voltage regulator module adjusts the voltage accordingly.

That said, the Core i9’s performance supposedly has nothing to do with heat, but power throttling by this module. At its current setting, the voltage regulator module “maxes out” due to overheating, which signals the motherboard to lower the processor’s speed of a minimum of 800MHz. Remember, this chip has a base speed of 2.9GHz.

Once the voltage regulator model cools down, the processor begins to consume more energy to reach its proper speeds. But as it launches up into its turbo speeds – a maximum of 4.8GHz — the cycle repeats again.

There is a way to fix the problem, but you do so at your own risk. The process involves putting the MacBook Pro into a custom System Integrity Protection state, so you can use unsigned kernel extensions. You’ll also need to download and install a tool called Voltage Shift that is available on GitHub.

By following the instructions, you can increase the Core i9’s performance by at least 20 percent. But the chip could do better, the Redditor suggests, if the MacBook Pro had adequate cooling and a better voltage regulator module. Apple could help increase the performance in a recall by swapping out the processor’s thermal paste, or by swapping out the heatsink with something that also cooled the voltage regulator module.

While new MacBook Pro owners are complaining about the Core i9 throttling, there is speculation that the performance decrease is a bit overblown. In recent benchmarks using Adobe Premiere Pro and Cinebench, the chip was shown to perform lower than a 2017 MacBook Pro equipped with an older Core i7 processor. Speculation suggests that the chip wasn’t the problem, but that the software simply isn’t optimized for six-core chips.

“Our Cinebench application has not been upgraded to measure the performance in a meaningful way,” Cinebench states. “The development team is aware and will be addressing this in the future.”

Whether the benchmarks are optimized or not, something is definitely going on in Apple’s new MacBook Pro, pushing numerous owners and testers to find a resolution. The voltage regulator module fix appears to be the current resolution, but only if you’re willing to risk damaging your expensive new MacBook Pro.

Editors’ Recommendations

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