When Apple announced the first three chips in its M3 processor family, the M3 Pro immediately stood out. Not because it was a huge leap over the prior generation, but because it was the first time we had seen Apple reduce key specs like transistor count, CPU and GPU core count, and memory bandwidth from one generation to the next.

Transistor count is an imperfect proxy for performance, but adding transistors is one of the primary ways to Boost a chip's performance (ramping clock speeds up is another, which we'll revisit shortly). The M3 and M3 Max feature substantial transistor count boosts compared to their M2 counterparts—from 20 billion to 25 billion for the M3 and from 67 billion to 92 billion for the M3 Max. The M3 Pro has 37 billion, down from 40 billion in the M2 Pro.

That didn't tell us much by itself, but it set us up to expect an M3 Pro that was a modest-at-best improvement over the M2 Pro. Now that we've been able to test one in a 14-inch MacBook Pro, we can confirm that this is the case. The M3 Pro is still decidedly faster than the regular M3, and building a chip with fewer transistors on a newer 3 nm manufacturing process has other benefits. But there's a wider performance gap between the M3 Pro and M3 Max than there was in the M2 generation, and you'll need to wait for the M4 generation before you see substantially faster Pro chips.

The makeup of the M3 Pro

Technically, the number of CPU cores included in the M3 Pro doesn't change from the M2 Pro, but the composition of those cores does change. Both have 12 cores in their fully enabled configurations, but M3 Pro has six high-performance cores and six smaller efficiency cores whereas M2 Pro had eight P-cores and four E-cores. This is likely where Apple saved most of those transistors.

Compared to the CPU, the M3 Pro's GPU doesn't take as large of a step back, but it decreases from a maximum of 19 cores to a maximum of 18, whereas the M3 Max goes from 38 to 40, and the vanilla M3 holds steady at 10. Memory bandwidth has also dropped from 200GB/s to 150GB/s. Memory capacity goes up a little, from 16 and 32GB to 18 and 36GB, which is handy.

We're testing the fully enabled version of the M3 Pro today, but there's also a partially disabled version available in the $1,999 MacBook Pro with 11 CPU cores (5 P-cores, 6 E-cores) and 14 GPU cores.

The one place where the M3 Pro is a solid step forward from the M2 Pro is in single-core CPU performance, where performance is up by around 15 percent thanks to a combination of architectural improvements and clock speed increases. Apple usually keeps its single-core performance pretty consistent up and down its entire chip lineup, and the M3 Pro performs nearly identically to the M3 Max in all of these single-core tests.

Multi-core performance is less impressive, and in these tests, the M3 Pro is almost exactly the same speed as an M2 Pro or M2 Max. There are a couple of tests here where the M3 Pro manages some low-single-digit improvements, but by and large, the performance gains of the individual P- and E-cores are roughly canceled out by the decision to replace two P-cores with E-cores instead.

GPU performance is a bit mixed. Compared to the M2 Pro, gains generally range from "statistically indistinguishable" (the Geekbench 6.1 test) to around 15 percent (the 3DMark Wildlife Extreme test), with most results falling somewhere in between. The M3 Pro GPU also gains hardware-accelerated ray tracing that older Apple GPUs don't have, and the media engine will decode AV1 video streams; you'll also need an M3 Pro rather than a regular M3 to connect more than one external display directly to your Mac. But these are differences that don't show up on charts.

Compared to the results in the GFXBench database, it looks like a fully enabled M3 Pro GPU comes in just a hair below the performance of the laptop version of Nvidia's GeForce RTX 4060, though "Windows vs. macOS" and "DirectX12 vs. Metal" are also variables to consider when trying to compare to PCs. It's at least in the same ballpark as what Dell is offering in a comparably priced XPS 15.

None of this is to say that the M3 Pro isn't "Pro." With 50 percent more P-cores and E-cores and 80 percent more GPU cores, people who buy an M3 Pro because they want more speed than an M3 offers should be mostly satisfied. But Apple has narrowed the gap between the M3 and M3 Pro while expanding the gap between the M3 Pro and M3 Max, all without changing prices (at least, not for the M3 Pro and M3 Max MacBook Pros).

Power-efficient Pro

There is one other area where the M3 Pro improves on its predecessor: power use under maximum load.

In our CPU-based Handbrake video encoding test, we found that the M3 Max was a lot faster than the M2 Max but that its peak and average power consumption was quite a bit higher. The M3 Pro is only a little faster than the M2 Pro in this test, but power consumption goes down quite a bit, from an average of 36 W to an average of 30 W.

This isn't a huge change, and measuring power use with software tools can be imprecise because you're relying on those tools to report power usage accurately. But using Apple's own powermetrics tool, the M3 Pro does better than any other Pro, Max, or Ultra chip we've tested in terms of the energy that the chip uses to accomplish a set amount of CPU-intensive work. Some M1 and M2 models are better on this front, but they also take almost twice as long to get the work done.

Previously, Apple's Pro and Max chips had the same CPU configuration and differed primarily in the GPU, where the Max series offered twice as many GPU cores as the Pro. For a lot of people, this was the right balance to strike since, despite accurate efforts on Apple's part, the Mac still isn't a destination for AAA games. But this occasionally created some weird overlaps in Apple's lineup, like the handful of months earlier this year when the M2 Pro Mac mini could outrun the M1 Max Mac Studio.

Despite modest-at-best gains in most of our tests, the benefits of a smaller M3 Pro chip to Apple are clear. A smaller chip will be cheaper to produce in the long run, padding Apple's profit margins and/or giving the company some latitude to keep prices level despite inflation and rising prices for any other components. Giving the Max a clear advantage in both CPU and GPU performance will also presumably push some users into upgrading who otherwise wouldn't have.

The M3 Pro is definitely the oddest chip Apple has released in the three years since Apple Silicon Macs became a thing. It's not worse than the M2 Pro in any metric, and it's slightly better in most, but it also seems to have been designed mainly to tweak the relative position of the Pro chips in the M-series family. Now that the M3 Pro's composition of cores has been rejiggered, we'll hopefully return to more straightforward generational performance gains with the next round of Pro chips sometime in 2024 or 2025.