They could in theory come off the same assembly line, that doesn’t mean the everything is identical.

Hell WD chips could be of higher quality as I am not suggesting I know their internal processes. I am saying things are optimized differently.

At this point of the conversation, you seem to be really grasping for theoretical stuff to defent Apple's margins with very little proof. Why?

I’ve said several times they could be using worse components.

The why I’m still talking is because people seem to think buying a gaming SSD is a good idea when they also want longevity / low risk of future. The parts can last 10+ years but they’re designed with something else in mind.

There really isn't much diversity in NAND flash product lines. Each generation of 3D NAND from WD+Kioxia basically consists of two sizes of TLC die and one or two sizes of QLC die. For the purposes of this conversation, binning doesn't matter because "SSD grade" is already the top bin. So the only variable on the NAND side for a high-end 2TB drive is the question of whether it's built with the high-capacity die (cheaper per GB), or twice as many of the low-capacity dies (potentially faster if it allows more controller channels to be fully populated, but that's usually not a problem at 2TB).

I’m not sure what you mean by SSD grade, Grade A to D chips aren’t strictly about binning but also traceability/fraud.

One hardware guy mentioned internal defects can cause differences is the amount of reserve sectors that a final product ends up with. That’s exactly the kind of arbitrary cutoff that lets companies charge different prices for the same part.

SSD-grade is the term used for flash with a low initial defect rate. See eg. https://www.szyunze.com/wp-content/uploads/2023/08/SpecTek-N... (from https://www.szyunze.com/spectek-unveiling-truths-about-degra... )

Lower-grade flash with higher initial defect rates is what gets used in USB flash drives and SD cards, and some bargain-bin SSDs with lower usable capacities (ie. 960GB rather than 1TB).

The stuff used in a WD Black or WD Blue branded consumer SSD is not a different quality grade from the stuff used in any other mainstream consumer SSD, Apple's included.

> They could in theory come off the same assembly line, that doesn’t mean the everything is identical.

It could just come down to different binning of the same part, and it would still make a difference.

> They're literally the same chips.

At what grade? Plus, how much extra endurance is baked in to Apple's drives, i.e. how over-provisioned are they?

My MacBook Air M1 reports 99% health after being daily driven (and some 26TB written to it) at work since 2020 (we got these as soon as they introduced), and I don't baby its drive in any way.

Any decent consumer SSD will be exactly the same, brands such as SK Hynix, Samsung, Crucial, WD, etc. same chips and same performance, much cheaper than the Apple tax.

I'll respectfully disagree on the performance front.

Any flash storage has two main components: A controller and a set of flash chips, and a third component enters to the picture when connecting these two: number & nature of channels.

Starting from the controller (and channels), beside the obvious PCIe generation, there are some other factors. DRAM support, NAND support (not all NAND is the same!), number of channels, and the speed of these channels. A DRAMless SSD will suffer after its "pseudo-SLC" cache runs out, and the performance of the drive will generally suffer if the number of channels can't absorb the traffic coming from the PCIe side. Here, to have a top notch SSD, you need to have a good/fast controller with DRAM support, and enough channels with enough speed to absorb all traffic requests, so you can get use of the premium NAND chips you bought.

Next, we have the flash layout. Flash chips vary in speed, density and drive. A high density flash chip might be slower, or a flash chip might require higher drive, resulting in higher temperatures in general. In some cases, instead of populating all channels, a manufacturer might decide to populate a few channels and leave the rest unpopulated, creating a big but slower SSD.

Beyond that, there are other considerations like over-provisioning at flash level, "soft SLC cache" size, wear leveling capabilities under sustained load, etc. etc.

For example, an enterprise SSD comes with the "same" TLC chips, but over-provisioned 5:1 or 10:1 (10TB flash for 1TB capacity)

Now, let's see some real-world examples:

- Kingston NV2, NV3: A budget SSD with great capacity and price. DRAMless, no channel number guarantee, and might come in with TLC or QLC chips. Burst speeds are OK, will make 90% of the people happy, but slows down in long transfers and under heavy load. Runs cooking hot in both controller and flash side.

- Kingston KC3000: A higher end drive with part/channel guarantees, handles sustained load better, runs way cooler, ironically.

- Samsung 980/990 Pro: Samsung's higher end drive. Runs cool, sustains speed all over due to DRAM and tons of channels and vertical integration of controller + NAND.

- Samsung T7 Shield: Looks like an bulky 1.8" drive, but it's selling point is it can sustain 1050MB/s writes wihtout even slowing down until it's full. Never gets warm.

So, flash drives comes in all shapes and sizes and with specifications and capabilities all over the place. A WD Blue and WD Black won't perform the same. Same for Sandisk's Plus, Extreme, Extreme Pro series.

This is why OWC was/is the go-to 3rd party SSD provier for Macs for quite some time. They tune their drives similar to Apple's and very similar to what OS expects as behavior. It's not slap some controllers and flash chips on a PCB, change three fields in a firmware and sell.

Flash storage is black magic at this point, and thinking every box is the same is a big mistake.

This comment can be easily 3x longer, but I want to keep it readable.