and"The Cortex-A55 serves as the successor of the ARM Cortex-A53, designed to improve performance and energy efficiency over the A53. ARM has stated the A55 should have 15% improved power efficiency and 18% increased performance relative to the A53. Memory access and branch prediction are also improved relative to the A53."
Let's stick to the Cortex-A55 boards for the moment, what can you buy at the moment?"The Cortex-A75 and Cortex-A55 cores are the first products to support ARM's DynamIQ technology. The successor to big.LITTLE, this technology is designed to be more flexible and scalable when designing multi-core products."
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Note the increased RAM size as compared to the earlier Cortex-A53 boards.
These specs seem to be given by marketeers rather than engineers, as I could not get any information as to the speed or bandwith of the Banana Pi M5 LPDDR4 RAM, and Hardkernel gives their RAM as having a 32-bit bus while Radxa claims to have 64-bit dual channel RAM.
Nor could I obtain any clear information as to the execution engines within the GPUs, as Hardkernel gives four for both the Mali G31 and G52, and Radxa gives only two for the Mali G52. Banana Pi doesn't even mention execution engines...and they are what's making your OpenCL go.