Intel: Fixes for Core CPU voltage bug won’t hurt performance

In Intel’s statement released on Friday, it says that its own recent tests of the microcode patches being rolled out to customers — for the voltage issue impacting 13th- and 14th-gen Core processors — basically show no performance impact, with exceptions on certain tests. Intel also said that “all future products” will not be affected by the bug.

Expect the performance impact of Intel’s microcode patch to be minimal

Back in 2023, researchers discovered that applying Intel’s patch for the “Downfall” bug affecting 6th- to 11th-gen Core chips could cut performance by up to 40 percent. Intel says that won’t be the case here. Any performance impact is within “run-to-run variation,” which implies that you wouldn’t notice any performance deviations.

“Intel’s internal testing — utilizing Intel Default Settings — indicates performance impact is within run-to-run variation (e.g. 3DMark: Timespy, WebXPRT 4, Cinebench R24, Blender 4.2.0) with a few sub-tests showing moderate impacts (WebXPRT Online Homework; PugetBench GPU Effects Score),” Intel said, not specifying what a “moderate” impact might be.

“For gaming workloads tested, performance has also been within run-to-run variation (e.g. Cyberpunk 2077, Shadow of the Tomb Raider, Total War: Warhammer III – Mirrors of Madness) with one exception showing slightly more impact (Hitman 3: Dartmoor). However, system performance is dependent on configuration and several other factors.”

The new microcode patches will still allow overclocking, Intel added, though with a standard disclaimer that doing so may void your system warranty. “For unlocked Intel Core 13th and 14th Gen desktop processors, this latest microcode update (0x129) will not prevent users from overclocking if they so choose. Users can disable the eTVB setting in their BIOS if they wish to push above the 1.55V threshold.”

Intel recently extended its warranty program on the affected Core processors to five years.

More on Intel’s Core CPU voltage bug

In Intel’s detailed statement, it summarizes the hard-to-find bug that has caused BSODs and other issues in Intel’s latest systems dating back almost to the beginning of the year. In late July, Intel said that issue was due to elevated operating voltages caused by faulty microcode that sent incorrect voltage requests to the processor.

“Intel’s current analysis finds there is a significant increase to the minimum operating voltage (Vmin) across multiple cores on affected processors due to elevated voltages,” Intel said in its statement. “Elevated voltage events can accumulate over time and contribute to the increase in Vmin for the processor. The latest microcode update (0x129) will limit voltage requests above 1.55V as a preventative mitigation for processors not experiencing instability symptoms. This latest microcode update will primarily improve operating conditions for K/KF/KS processors.”

Intel said it’s continuing to explore further mitigation options to combat what it called “Vmin shift” on Core chips, and will provide further updates by the end of August.

How the patch will be rolling out

To date, Intel has released three “mitigations” to solve the problem: the “default settings” option in May, plus two microcode patches. June’s patch (0x125) to fix the Enhanced Thermal Velocity Boost (eTVB) was supplemented by the August patch (0x129) that’s now rolling out to board and system makers.

Intel’s statement stressed that the patch would not be rolling out via Windows Update. If you’re affected, you’ll need to download the code either from your motherboard maker’s support site or from the PC maker if you own a pre-built system.

Intel previously provided a list of the affected Intel Core desktop processors and said that mobile Core chips are not affected.