I suppose in fairness and to the explanation it does give, the other thing that footprint allows is a shorter path for the pins that would otherwise be near the ends of the daughter board (e.g. on a DIMM), since they can all go roughly straight across (on multiple layers) instead of a longer diagonal according to how far off centre they are. But even if that's it, that's what I mean by it seeming incomplete. :)
All the traces going into the slot need to be length-matched to obscene precision, and the physical width of the slot and the room required by the "wiggles" made in the middle traces to length-match them restrict how close you can put the slot. Most modern boards are designed to place it as close as possible.
LPCAMM2 fixes this by having a lot of the length-matching done in the connector.
And all this is needed even though the DRAM signaling standard has extensive measurement and analysis of the traces built right into the hardware of the DRAM and the memory controller on the processor. They negotiate the speed and latency at runtime.
Giant pain.
They are going to lose money when people buy new RAM, rather than a whole new laptop. While processor speeds and size haven't plateaued yet, it's going to take a while to develop significant new speed upgrades and in the meantime, the only other upgrade is disk size/long-term storage, which, aside from Apple, they don't totally control.
So, why should they relenquish that to the user?
It makes sense that the first ones to use this new standard would be Dell and Lenovo. They both have "business" lines of computers, which usually offer on-site repairs (they send the parts and a technician to your office) for a somewhat long time (often 3 or 5 years). To them, it's a cost advantage to make these computers easier to repair. Having the memory (which is a part which not rarely fails) in a separate module means they don't have to replace and refurbish the whole logic board, and having it easy to remove and replace means less time used by the on-site technician (replacing the main logic board or the chassis often means dismantling nearly everything until it can be removed).
Alternatively, it allows them to use more efficient RAM in computer lines they can't make non-repairable so they can boast of higher battery life.
- the manufacturer themselves benefit from easier to repair machines. If DELL can replace the RAM and send back the laptop in a matter of minutes instead of replacing the whole motherboard to then have it salvaged somewhere else, it's a clear win.
- prosumers will be willing to invest more in a laptop that has better chance to survive a few years. Right now we're all expecting to have parts fail within 2 to 3 years on the higher end, and budget accordingly. You need a serious reason to buy a 3000$/€ laptop that might be dead in 2 years. Knowing it could weather RAM failure without manufacturer repair is a plus.
You're thinking about this the wrong way around.
Suppose the user has $800 to buy a new laptop. That's enough to get one with a faster processor than they have right now or more memory, but not both. If they buy one and it's not upgradable, that's not worth it. Wait another year, save up another $200, then buy the one that has both.
Whereas if it can be upgraded, you buy the new one with the faster CPU right away and upgrade the memory in a year. Manufacturer gets your money now instead of later, meanwhile the manufacturer who didn't offer this not only doesn't sell to you in a year, they just lost your business to the competition.
They are going to buy the 800$, any of the two, complain when it inevitably "works slower" in a couple of years (if they are lucky), and buy a new 800$ once again then. I don't see the manufacturer's motivation to offer upgradable RAM.
So it's the egg and the chicken where if it'll be important to consumers, it might end up as catching up.
From what I gathered, it's around a watt per when idling (which is when it's most critical): the sources I found seem to indicate that ddr5 always runs at 1.1V (or more but probably not in laptops), while lpddr5 can be downvolted. That's an extra 10% idle power consumption per.
do storage next.
A lot has changed.
God forbid someone steps on it too, I think I might still have some scars on my feet.
It's true for any laptops that can be reasonably described as having a "SoC" and not CPU, anyway.
(I guess you could be extremely pedantic and try to argue that T2 counted as SoC? But clearly not what I meant.)