We know quite a lot about the upcoming Google Pixel 7 and Pixel 7 Pro, but the chipset that will power those phones remains a little mysterious. Whether it was a benefit or a curse, Google's sticking with its custom chips, and the Pixel 7 will debut a new incarnation of Tensor: the GS201. And, like last year, what little we do know is pretty unusual.
So far, leaks for the upcoming Tensor G2 — it's official name, according to Google's website — haven't happened at the same rate they did for the original Tensor chipset. By just April of 2021, we knew quite a lot about the original GS101, but Google has managed to keep a tighter ship this year, limiting how much we and plumping out the spec table with plenty of “unknown” labels.
For those that just want a table, here you go:
|Dev board code name||Cloudripper|
|Model number||GS201, Tensor G2|
|Cores||2x super-big ARM Cortex-X1, 2x big A76, 4x small Cortex-A55|
|Manufacturing node||4nm Samsung PLP|
The Tensor G2 will be made by Samsung on its 4nm node using what's called panel-level packaging. This is a complicated way of saying the chips will be carved out of a square wafer rather than a round one, reducing waste. This likely won't have much impact on the chip's performance in actual devices, but it's nifty and might reduce costs — potentially useful when we're still in the middle of a chip shortage.
According to some recent diving into the boot logs of a Pixel 7 Pro prototype and further corroborated by a Geekbench benchmark spotted by developer Kuba Wojciechowski on Twitterthe Tensor G2 is all but confirmed to keep the 2+2+4 core cluster configuration that the original Tensor GS101 used, with two “super-big” cores, two more typical big cores, and four small cores. Details in the logs and the Geekbench results show that the small cores in the G2 are still Cortex A55s. The log even makes a note of a workaround implemented specifically for them. These are the same small cores used in the original GS101 Tensor chipset and a design that dates back to 2017.
The other cores in the G2 are now also confirmed to remain the same across the first-gen Tensor and the G2. The last-gen Tensor used ARM Cortex-X1s for its “super-big” cores and A76s for its big cores, and the same seems to be true for the G2.
One of the things that does change across generations is the frequency. The A76 cluster is 100MHz faster at 2.35GHz while the X1 cluster has been bumped up by 50MHz, which gives it a frequency of 2.85GHz. This seems to have translated to a 10-15% better result in Geekbench, though it remains to be seen how this synthetic result translates to real-world usage.
It looks like Google is upgrading the GPU, though. Wojciechowski found that the Geekbench results mention the Mali-G710 GPU rather than the G78. It should provide about 20% better performance and efficiency. The new GPU is supposed to help the on-board machine-learning focused TPU a 35% boost in applicable processes. The TPU itself is also seeing an upgrade.
Unsurprisingly, the G2 will be paired with a Samsung-made modem again, according to details divined in earlier teardowns and the Geekbench results. The specific model spotted this time is the g5300b, which is all but confirmed to be the Exynos Modem S5300.
This small design upgrade might seem disappointing on paper, but it could make a lot of sense on the performance to power usage ratio. Newer processors are found to improve performance at the cost of energy consumption, so sticking with the older generation might actually leave more room for better efficiency. It also helps that Google already has experience with this setup for a whole generation, making it simpler to further optimize the system. This is somewhat reminiscent of the company sticking with the same camera for multiple generations of Pixel phones.
Mass manufacturing for the chipset is estimated to have begun in June 2022, according to one report. This makes sense, as Google had to get enough Tensor G2s ready for the Pixel 7 and 7 Pro launch on October 6, 2022.
Smartphone chipsets aren't just a list of cores; other details inside them can affect performance. One of the biggest reasons that Google elected to create its own chipset with the original Tensor was for enhanced machine learning applications. With the rise of ambient computing, so-called heterogeneous compute — which means pushing specialized workloads to different or customized pieces of hardware rather than just general-purpose CPUs — arguably has a bigger impact on perceived device performance than big single-threaded gains. It's not just about one or two big benchmarks, but how we actually use our phones. More and more, that's for things like speech recognition, translation, fancy camera features, AR/VR, and other more highly specialized workflows. And for that, you need more than a handful of recent ARM cores and a GPU.
The original Tensor included parts of Google's HDRNet image processing pipeline in hardware, providing more specialization and direct performance for Google's workloads than a general purpose ISP can. Google also gave it a dedicated security core (paired with a separate Titan M2 chip running “Trusty OS”). While details like these haven't leaked for G2 yet, you can likely bet that Google will continue to add these sorts of highly specialized changes. After all, features like these are the entire reason why a company would opt to create a custom smartphone chipset. Otherwise, Google would have just used something from Qualcomm, as it did in the past.
Details haven't leaked yet, the G2 will almost certainly have further optimizations and improvements in Google's heterogeneous compute strategy, implementing other new camera and machine learning features in hardware where they can be done more quickly and efficiently. At I/O, all Google said about the upcoming chipset was that it will bring “even more AI-heavy breakthroughs and helpful personalized experiences across speech, photography, video, and security.” And while the original GS101 Tensor was heavily based on Samsung's Exynos designs, we might see future models, like Tensor G3 (if it will be called that), diverge from this base over time and as Google's requirements change.
It's also worth pointing out that Google's 2+2+4 core configuration is unique. So far, other chipset manufacturers haven't followed in Google's footsteps by including more than one “super-big” core. In an interview with Ars Technica's Ron Amadeo, Google's Phil Carmack (VP and GM of Google Silicon) said that this specific configuration was chosen to increase efficiency at “medium” workloads by being able to throw more resources at a task to do it quickly, returning to a low-power state faster:
“When it's a steady-state problem where, say, the CPU has a lighter load but it's still modestly significant, you'll have the dual X1s running, and at that performance level, that will be the most efficient… You might use the two X1s dialed down in frequency so they're ultra-efficient, but they're still at a workload that's pretty heavy. A workload that you normally would have done with dual A76s, maxed out, is now barely tapping the gas with dual X1s.”
The Tensor G2 will debut with the Pixel 7 series of phones, which includes the Pixel 7 and Pixel 7 Pro. Google has set a date for its next hardware launch: October 6th. That's when we'll finally get our first glimpse of exactly what kind of power Tensor G2 contains. If history is any indicator, we might see it also come to a future a-series Pixel (probably the Pixel 7a in 2023). Google has plans to release a Tensor-powered tablet as well, though we expect it will use the first-gen GS101 chipset when it lands in 2023.
Another hardware codename has been tied to the G2, but based on the name itself — Ravenclaw, a portmanteau of “Raven” (Pixel 6) and “claw” for the big cat names of the Pixel 7 series (Cheeta and Panther) — that might be a test device meant to include the Pixel 7 hardware inside a Pixel 6 body. Google used a similar naming schema for a Pixel 5 that had Pixel 6 internals.
Made by Google
With Tensor G2 reported entering production as of June 2022, the rate of leaks regarding the upcoming chip will likely pick up soon, and Google also has a history of taking charge during leak season to dribble out its own feature highlights. Odds are we'll know more very soon. The longest we'll have to wait, in either case, is until October's Made by Google event when the Pixel 7 series will finally debut.