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trashcanman | 2 years ago

The storage and memory upgrades are expensive and also have a penalty in terms of power. Memory draws the same current regardless of if it’s being used and that is significant. Unified memory is also very different, has much higher bandwidth than RAM and lower latency. You can’t compare unified memory with RAM.

As far as the SSD, the base option comes with one 256GB NAND flash IC, where if you upgrade to 512GB they have to add a second. That matters because adding a second means you double the IO bandwidth using their current design. It’s something like 3500 vs 7500 MB/s. If you add more NAND modules you also scale up the IO speed further but the difference between 3500 and 7500 is significant for all workloads where above that you probably won’t see a gain except in niche applications like video editing, assuming you have the complimentary processing power and unified memory to utilize that throughput. For storage, Apple provides 2TB cloud service for $10/mo and these have wifi 6E so it’s cheaper to use the cloud than buy the storage, assuming it’s not working storage, and safer too.

Also, upgrades on Apple products hold their market value very poorly. The M2 studio just came out and maxed out M1 units are on sale NIB at 1/4 price of retail from 3 months ago, which is not at all a true quantification of performance since the M2 is only what 15-20% faster.

So after quite some research for the MBA 15; 16GB + 512GB + 70W adapter is the optimum for power draw, performance, cost and value preservation.

Overall, it seems the best value strategy with Apple products is to take the first upgrade for memory and storage and leave it at that. You can then resell every year and recoup 60% and upgrade to the latest w a new battery. Apple is actually very cheap after the first investment considering the productivity and time saving benefits, and you can’t steal an Apple device. Just don’t drop it

Also if you are considering big upgrades, compare the cost to just buying two base units as the base units are way closer to the manufacturing cost. Often there is more benefit to having two expendable units and they will hold their resale value better.

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sudosysgen|2 years ago

Unified memory literally is RAM. It's just LPDDR5. It might have better timings, due to being located closer, that's it. The framework 16 also does DDR5-5600, so you get 100GB/s of bandwidth with a dual rank memory setup.

In theory you'd take a latency hit, but in reality (at least the M1) was limited by it's memory controller and had DRAM latencies of ~100ns, which is actually worse than Zen 4 at ~70ns. This is because before querying RAM, you first need to query every level of cache, and then you hit the latency of the DRAM itself, so the actual distance is not a dominant factor.

So no, unified memory doesn't give any actual performance advantage. It could in theory (and marginally), in practice it's just marketing.