Arm has just unveiled its next-gen processor technologies for upcoming smartphones, which could potentially land in consumer hands as soon as the end of the year. As usual, we have new CPU and GPU parts to cover, but there are also a lot of subtle changes to the familiar formula to get our heads around this year as well.
That’s hardly surprising, the landscape has changed quite rapidly in the last twelve months. Qualcomm has gone down the custom Arm-based CPU route with the Snapdragon 8 Elite, resulting in fewer high-profile flagships using Arm IP this year. At the same time, Google has moved to Imagination Technologies for graphics, while the rapid advancement of AI has thrown a spanner in traditional performance metrics. Arm’s latest announcement moves to address at least some of these challenges.
First up is another rebrand. Last year’s Cortex-X and A monikers give way to new C1 CPUs, which are divided into Ultra, Performance, Pro, and Nano cores. We’ll get into all this in a minute. Graphics has undergone a slightly less drastic rename; Mali remains, but the short-lived, high-end Immortalis gives way to a far simpler G1-Ultra, Premium, and Pro branding.
Arm
Another notable change is that Arm is taking a greater role in platform design and turnkey solutions. In other words, designs that are ready to plonk right into a chip. I’m still a little unsure about what this means for the traditional individual part licensing structure. Arm insinuates that flexible platform customization remains, and I assume customers can still cherry-pick specific CPU and GPU parts if they want. Still, Arm aims to speed up time to market with its more tightly integrated platform and close relationships with foundries like TSMC. By the way, platform options that contain C1-Ultra and Premium cores fall under the Arm Lumex branding umbrella.
With all that jostling around in the back of our brains, it’s time to examine what’s new on the hardware side.
Meet Arm C1, from Ultra to Nano
Arm
With the new Arm C1 names comes a subtle shift in the architecture. All of the new cores are bumped up to ArmV9.3, which means we say goodbye to mixing and matching with previous Cortex-X and A models. That’s right, there won’t be any more multi-tier Cortex-X parts in this year’s chipset announcements. Still, C1-Ultra and Performance can be considered successors to the Cortex-X925, the C1-Pro is the new middle-core that replaces the Cortex-A725, and the C1-Nano is the revamped Cortex-A520. So we’re still looking at three different microarchitectures. The difference between the C1-Ultra and Performance is that the latter is optimized for a 35% smaller area footprint, making it cheaper for upper-mid-tier chipsets but with a slight performance penalty.
Speaking of performance, IPC gains (those for the same clock speed, cache configuration, etc as last year) are reasonable but perhaps not as groundbreaking as you might expect from the rename. The Arm C1-Ultra appears to be in the region of 12% faster than the Cortex-X925, a ballpark I’ve pulled from a rather poorly labeled graph we saw. However, this increases to 25% once you factor in the move to 3nm and the higher clock speed potential of a 4.1GHz C1-Ultra versus a 3.6GHz Cortex-X925. Perhaps the bigger deal is that the C1-Ultra can offer the same performance as last year while consuming 28% less power.
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