Exactly. If you have the latest and greatest mobile phone and 8GB (or 12GB) of LPDDR5 on a Snapdragon 8 Gen 2 soc you still only have 8.5 Gbps memory bandwith (max, less in actual phones running it at slower speeds). That's 1 GB/s. An ivy bridge i5 3570k has a memory bandwidth of 25 GB/s. Even an ancient Core 2 Duo has 5GB/s memory bandwidth at stock speeds. Phones are very bad at computing tasks outside of "watching video" "buying things online" and the like.

Something is really off with your calculations. High-end Snapdragon chips are running with at least 64-bit busses, combined with the clock speed advantages LPDDR5 should put it well ahead of any 128-bit DDR3 system. At least 50GB/s.

The real reason phones are bad at computing tasks is they throttle when put under any sustained load.

I'm seeing a lot of specs for that chip listing 64Gbit/s and some showing GB/s. I'd love to see some confirmation of actual performance.

Depending on clock speed of memory. For LPDDR5-6400 which is pretty common.

3200000000(clock) x 2(DDR) x 2(16-bit channel width) x 4(channels) = 51200000000 bytes/sec or 51.2 GBytes/sec

16 bits is where you added data width here, so that would be 52 gigabits a second, no? To go to bytes wouldn't we need to divide by 8?

And I imagine this commenter talking about 8GB RAM, they're assuming not all 4 channels are populated. So one could imagine two channels being populated, 25.6 Gbit/sec, divide by 8 to get bytes, that's then only 3.2GB/s?

I multiplied by 2 instead of 16. That's what makes it bytes.

Ah ok I see what you did there, thanks for the explanation.