ARM took another step towards facing Intel and AMD on their own turf today. The new Cortex-A78C is based on the high-performance Cortex-A78 architecture that ARM announced earlier this year, but with some specific optimizations and configurations intended to help the chip compete in the laptop market.
The Cortex-A78C is part of the newly-announced Cortex-A78 family of products, including the Cortex-A78AE for automotive and embedded applications, and the Cortex-A78 for the smartphone market.
The Cortex-A78C will offer better performance than any existing ARM chip for laptops, if only because it brings more firepower to bear. ARM laptops to-date have used chips with a mixture of big and little cores, typically in a 4+4 configuration. The A78C is specifically designed to offer eight cores worth of “big” CPU performance, with either 256KB or 512KB of L2 cache per-core and up to 8MB of L3 cache for all the CPUs to share collectively. ARM does note that this is an “up to” configuration, so we could theoretically see A78C CPUs with 4-6 cores. L1 cache size is also variable, at either 32KB for each of the instruction and data caches, or 64KB. The L3 cache supports up to 60GB/s of sustained bandwidth (presumably that’s to any single core or to the entire chip simultaneously).
To-date, the performance of ARM CPUs on Windows has been unimpressive, but at least some of this is due to the fact that the chips are often running emulated code. While there’s a lot of attention focused on Apple’s upcoming ARM launches, Apple’s ARM CPUs have much higher single-threaded performance than the Cortex chips ARM has traditionally designed itself. The Cortex-A78C will improve overall performance thanks to its larger caches and higher, more-powerful core counts, but Apple appears to be the only other company within realistic striking distance of x86 performance — and given how little we know at this point, it’s premature to be making any strong predictions of how AMD and Intel will compare.
improving the performance of Windows on ARM devices by scaling up hardware designs is the fastest way for ARM to build market share and buzz around these products, as opposed to waiting and hoping software devs take notice. The closer ARM can drive the performance comparison in hardware, the more attention they’ll get for their platforms over time.
I got into a discussion last night about ARM vs x86 on traditional PCs, and the best I can figure is that it's just not needed. Yes they have their benefits, and I think most will point to Apple's ARM based chips for a prime example, but Apple is Apple, a very closed system with a very limited number of configurations, and the upcoming ARM based Macs will lose Boot Camp and with it Windows and all programs relying on x86. Even Windows 10X is going to launch without Win32 compatibility, and we know how badly that went over with WinRT and Win10S, and 10X is supposed to be Microsoft's launchpad for an ARM based Windows system.
But my biggest stance about ARM on traditional mainstream x86 laptops and desktops is that whatever efficiency ARM brings to the table, it's not going to provide any meaningful benefit over x86. Thanks to AMD Renoir we know that a powerhouse of a CPU can be put into a laptop that isn't as big as a suitcase or cost more than a down payment on a new car yet provide excellent battery life and performance, and on the desktop front where heat production is more important than power consumption, computational power-per-watt has never been higher and is only expected to grow greatly in the next two years with Zen 4.
In the future I can see ARM replacing x86, but it's just now starting to attack the server market, and that's where ARM's benefits over x86 are the most needed, but as far as most every other market, it's going to take x86 emulation at >95% speed if ARM has any hope of replacing x86 for a long time to come.
One thing is for sure is that you now have 3 companies showing they can compete if not beat Intel. 2 ARM cpu makers and AMD in the x86 market. Emulation is pretty good and will only get better. I can absolutely see a near future where it just wont matter. Most consumers won't care what is under the hood. They will care more about price and how long it lasts before charges even before top performance. Regardless it is great competition that will only make all involved strive for better tech and help keep prices down.