A chance at the benchmark crown? —

Shocking Pixel 6 rumor lists Google SoC with two ARM X1 CPU cores

Google blazes its own trail for its first SoC design.

What in the world is going on?

Google is building the Pixel 6, and with it, the company is dumping Qualcomm and introducing its first in-house main SoC (with help from Samsung): the "Google Tensor SoC," aka "Whitechapel." Other than some talk about Google's special AI sauce, there's hasn't been much info about the core parts of Tensor like, say, the CPU. A reasonable expectation for a company building its first SoC is that it won't be too ambitious—we would expect Google to play within the guardrails set up by ARM, and after shipping a modest, cookie-cutter SoC, the company would learn from its first design and iterate. But a new report from XDA Developers' Mishaal Rahman claims that even with its first design, Google isn't afraid to blaze its own trail in SoC design.

Recall how ARM SoCs generally come with three tiers of CPU cores: a big CPU for bursty processing tasks like app-launching, medium cores for sustained performance, and small cores for background duty and low-power processing. Rahman says he has a source with a real-life Pixel 6 Pro and offers the following CPU specs: two 2.8GHz Cortex-X1 cores, two 2.25GHz Cortex-A76 cores, and four 1.8GHz Cortex-A55 cores.

If that information is true, Google's lineup of CPU cores will be unlike anything else on the market. Qualcomm's Snapdragon 888 and Samsung's Exynos 2200 both have one Cortex X1, three Cortex A78s, and four Cortex A55s. You aren't supposed to have two X1 cores. These are the big cores that can do some serious processing, and cramming two of them into a smartphone could lead to incredible performance. Or it could lead to extreme overheating. You're also not supposed to use A76 cores, which are from last year. Every other company's "medium" cores are the newer, faster A78 cores.

Compared to the typical design, Google swapped out one of the medium cores for a second big X1 core and then turned down the remaining medium cores by switching to cores from last year. Maybe downgrading the remaining medium cores is an attempt to balance the heat output? At launch, ARM said a 5 nm Cortex A78 had 20 percent better-sustained performance in the same thermal envelope as a 7 nm Cortex A76. But since Google is using 5 nm A76s, the A76 cores should be putting out less heat than the A78.

Frankenchip

So what exactly is the goal here? Is Google trying to seize the Android benchmark crown with this dual X1 Frankenchip? It would be a shame to spend all these engineering resources on a custom solution and turn in a medium-performance benchmark when chips with medium-performance benchmarks are readily available, out of the box, from several vendors. There's a lot of effort being spent here that will hopefully pay off somehow.

The Android community's collective head-scratching Tensor journey started with this surprise entry in the Geekbench 5 database, which lists a "Google Pixel 6 Pro" with that unprecedented 2 x 2 x 4 core layout. Geekbench info reads from an easy-to-fake file, but this entry didn't seem like a fake since it was already completely unbelievable on its own. Rahman says, "The build fingerprint, kernel version string, CPU frequencies, CPU clusters, GPU info, and more match the values from our source’s Pixel 6 Pro." So it is very likely that this entry shows a legit Geekbench run.

And for a flagship smartphone, this Geekbench 5 score is terrible. A Snapdragon 888 scores somewhere in the range of 3300-3500, while Google's Pixel 6 is scoring lower than a Pixel 4. We would guess that this is due to lots of optimization and configuration work that still needs to be done and that it would be wrong to draw any conclusions from the score.

We're starting to get a clearer picture of what's in the Google Tensor SoC, even if the real-world performance is still a wild card. Samsung's Exynos unit is helping design the chip, and the other core components are very Samsung-y. The GPU is reportedly the same as the Exynos Galaxy S21, an off-the-shelf ARM Mali G78. The modem is also from Samsung (an Exynos 5123), which will mark the first time in a while that an Exynos modem has come to US shores. Google is hyping up the AI-centric parts of the chip design and promises that the chip will power onboard voice transcriptions.

Because it has access to someone with a Pixel 6 Pro, XDA was also able to corroborate plenty of the other specs that have been floating around. The Samsung-made 50MP "GN1" image sensor for the main camera represents the Pixel line's first image-sensor upgrade in several years. That rectangular camera part is a 4x optical telephoto lens powered by a Sony 48 MP IMX586, while the wide-angle camera continues Google's love affair with Sony image sensors from 2016—it's a 12 MP IMX386.

Other reported specs promise a computing powerhouse with a huge 5000 mAh battery, 12GB of RAM, 128GB of storage, and Wi-Fi 6E. After taking a year off with the Pixel 5, Google seems to be returning to the flagship race.

Google's Tensor SoC gets a promotional bag of potato chips—but only in Japan.
Enlarge / Google's Tensor SoC gets a promotional bag of potato chips—but only in Japan.

Google is certainly hyping the Google Tensor SoC in its advertising. In Japan (which is apparently Google's new second-favorite country), the company is celebrating its first-ever in-house SoC by selling "Google Original Chips" on the Google Store—these are literally bags of edible potato chips, styled after each color of the Pixel 6. They all come in a "Googley Salty Flavor" and even have a big stripe across them to match the camera block. The video ad for the chips—in which a woman charges a bag of Pixel potato chips with a USB-C plug—is really something.

We still have no idea when this phone is actually coming out. Android 12 is rumored for October 4—so a release would presumably be sometime after that.

Listing image by Google

Channel Ars Technica