AnTuTu is a software benchmarking tool commonly used to benchmark phones and other devices to showcase their processing speed. The higher the number that Antutu produces after the benchmarking process, the faster the processor is considered. It is a helpful rule of thumb to compare Android headunit speeds.
Always try to compare apples with apples. e.g. 4Gb compared to 4Gb. This is not always possible because some ancient processor units will only work with 2 GB RAM, but these are best avoided anyway.
AC8257 vs PX5
So in this challenge, the 9000 benchmark of the AC8257 beats the 4000 benchmarks of the PX5. From this, you can see a helpful jump in benchmark numbers that the AC8257 has over the PX5 chip. This jump in processor performance is noticeable in everyday use when booting up from cold or loading more intensive apps.
With both processors having the same usable RAM, the AC8257 is faster than the PX5, but the PX5 is still a usable Android headunit. So, don’t just focus on the speed; also look at other features you want, like RGB, DSP, or even your budget. But if everything else is equal, the faster SoC will perform faster under heavier and newer apps than a slower chip.