Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

ifixit.com

Post reply on HN
Print view View original

81–90 of 171 posts

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#81

Post by bmicraft »

kjkjadksj wrote: post #75
magicalhippo wrote: post #39

Earlier quoted context omitted.

The physical size of the socket and having the connections on the edge means you're forced to have much longer traces. Longer traces means slower signalling and more power loss due to higher resistance and parasitics. This[1] Anandtech article from last year has a better look at how the LPCAMM module works. Especially note how the connectors are now densely packed directly under the memory chips, significantly reduci…

I'd wager for most consumers capacity is more important than bandwidth and the power losses are going to be small compared to the rest of the stack.

Bandwidth translates directly into better (igpu) performance

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#82

Post by Rohansi »

wmf wrote: post #49
mschuster91 wrote: post #45

Earlier quoted context omitted.

> Don’t forget - they solder in the flash too even though there is no technical reason to do so. There is, Apple uses flash memory as swap to get away with low RAM specs, and the latency and speed required for that purpose all but necessitates putting the flash memory directly next to the SoC.

This is not really true; Apple's SSDs are no faster than off-the-shelf premium NVMe SSDs.

Yeah but some people need to justify their $1,800 USD purchase of laptop that comes with only 8 GB of RAM. Even though most laptops manufactured today would also come with NVMe (PCIe directly connected to the CPU, usually) flash storage, which is used by all operating systems as swap.

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#83

Post by redeeman »

baby_souffle wrote: post #4

This is fantastic news. Hopefully the cost to manufacturers is only marginal and they find a suitable replacement for their current "each tier in RAM comes with a 5-20% price bump" pricing scheme. Too bad apple is almost guaranteed to not adopt the standard. I miss being able to upgrade the ram in macbooks.

and they wont so long as people buy regardless

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#84

Post by redeeman »

jcotton42 wrote: post #32
oneplane wrote: post #28

On the other hand, with a reflow station everything becomes modular and repairable. I do hope that a more widespread usage of compressed attachment gives us some development in that area where projects that were promising modular devices failed (remember those 'modular' phone concepts? available physical interconnects were one of the failures...). Sockets for BGAs have existed for a while, but were not really end-use…

> On the other hand, with a reflow station everything becomes modular and repairable. Not for the average person.

true, but can the average person replace the innertube on a bicycle wheel? :)

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#85

Post by Tuna-Fish »

OJFord wrote: post #53
orev wrote: post #14

I’m glad they explained why RAM has become soldered to the board recently. It’s easy to be cynical and assume they were doing it for profit motive purposes (which might be a nice side effect), but it’s good to know that there’s also a technical reason to solder it. Even better to know that it’s been recognized and a solution is being worked on.

I didn't find that a particularly complete explanation - and the slot can't be closer to the CPU because? - I think it must be more about parasitic properties of the card edge connector on DIMMs being problematic at lower voltage (and higher frequencies) or something. Note the solution is a ball grid connection and the whole thing's shielded. I suppose in fairness and to the explanation it does give, the other thing…

> and the slot can't be closer to the CPU because?

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.

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#86

Post by freedomben »

leduyquang753 wrote: post #16
farmdve wrote: post #9

Remember that Haswell laptops were the last to feature socketed CPUs. RAM is nice to upgrade, for sure. As well as an SSD, but CPUs are still a must. I would even suggest upgradeable GPUs but I don't think the money is there for the manufacturers. Why allow you to upgrade when you can buy a whole new laptop?

The Framework laptop 16 features replaceable GPU.

I'm writing this from my Framework 16 with GPU and it is the best laptop I've ever known. It's heavy and big and not the most portable, but I knew that would be the case going into it and I have no regrets

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#87

Post by masklinn »

kjkjadksj wrote: post #73
orev wrote: post #14

I’m glad they explained why RAM has become soldered to the board recently. It’s easy to be cynical and assume they were doing it for profit motive purposes (which might be a nice side effect), but it’s good to know that there’s also a technical reason to solder it. Even better to know that it’s been recognized and a solution is being worked on.

They can have their technical fig leaf to hide behind but in practice, how many watts are we really saving between lpddr5 and ddr5? is it worth the ewaste tradeoff to have a laptop we can't modularly upgrade to meet our needs? I would guess not.

> how many watts are we really saving between lpddr5 and ddr5?

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.

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#88

Post by throwaway48476 »

OJFord wrote: post #53
orev wrote: post #14

I’m glad they explained why RAM has become soldered to the board recently. It’s easy to be cynical and assume they were doing it for profit motive purposes (which might be a nice side effect), but it’s good to know that there’s also a technical reason to solder it. Even better to know that it’s been recognized and a solution is being worked on.

I didn't find that a particularly complete explanation - and the slot can't be closer to the CPU because? - I think it must be more about parasitic properties of the card edge connector on DIMMs being problematic at lower voltage (and higher frequencies) or something. Note the solution is a ball grid connection and the whole thing's shielded. I suppose in fairness and to the explanation it does give, the other thing…

Competes with space for VRM's.

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#89

Post by masklinn »

cesarb wrote: post #64
drivingmenuts wrote: post #46

Earlier quoted context omitted.

The problem is getting manufacturers to implement the new RAM standard. While the justifications given are great for the consumer, I didn't see any reason for a manufacturer to sign on. 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…

> While the justifications given are great for the consumer, I didn't see any reason for a manufacturer to sign on. [...] 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 (o…

> To them, it's a cost advantage to make these computers easier to repair.

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.

Re: LPCAMM2 is a modular, repairable, upgradeable memory standard for laptops

#90

Post by masklinn »

wtallis wrote: post #66
sharpshadow wrote: post #65

Is it possible to have both LPDDR and LPCAMM2 in use at the same time?

LPCAMM2 is a connector and form factor standard for modules carrying LPDDR type memory chips.

I assume they mean having some memory soldered and an expansion slot.

I've seen laptops like that, with e.g. 8GB soldered and a sodimm slot.

Post reply on HN