Dell's DDR5 CAMM Appears in More Detail, Comes in Several Shapes, Won't be Proprietary

[lexluthermiester]

Can the PCB underneath have other components, or does it have to be empty?

Sure, no reason why it can't..

 

[dyonoctis]

Thinner?

Who cares?! The height of a SODIMM slot isn't the thing that prevents laptops from getting thinner, it's the thickness of heatpipes and their associated cooling fins. Make those too thin and you get machines that thermally throttle with woeful little high-pitched fans that can barely handle a 15W TDP
*cough* Apple *cough* Dell XPS *cough*.

No thanks, laptops are already thin enough and the benefit of having an almost unnoticeably thicker chassis is that the speakers can be a little bit less godawful and the battery can be very slightly larger.

Who the hell is asking for thinner laptops anyway? They're already so thin that they're horrible to type on and way too fragile....

And also, faster. current SoDimms are not really know for groundbreaking speed and tight timing

This is what I'm saying, that's a lie presented to you by manufacturers for why they solder the RAM onto the board. They do it because it's a cost-saving for them, and they can force/persuade buyers into CPU/Screen/SSD upgrades they weren't necessarily interested it by segmenting the larger RAM capacities to those upgraded SKUs. Sadly it's an incredibly anti-consumer practice that has been obscured by easily disproven claims that it's for reducing the height.

I have one of the thinnest 15" laptops on the market, an Envy X360 and it has two SODIMM slots:

View attachment 245078
View attachment 245079

Even with an EMI shield over the top, and it being directly under the keyboard deck, The SODIMM slots are still not the limiting factor in the laptop's thickness:

• The speakers and the battery are both each as tall as the keyboard, motherboard, SODIMMS and EMI shield combined
• The keyboard deck actually flexes a little on the right because there's no RAM behind like on the left side to fill the void between the fans and the battery.
• The rear exhausts for the two fans are laughably thin slits because the laptop is no taller than a USB-A and HDMI port at it's thickest point. Even with two fans, this thing is very audible at just 25W cTDP and it spends most of its time at 15W because that's all the fans can handle quietly.

This thing is entirely limited by the thickness of the battery at the front and the already-far-too-slim cooling system at the back. There's loads of empty space in the middle for chunkier components and absolutely no advantage to replacing the SODIMMs with something thinner; All that would do is increase the keyboard flex. I guess in an ideal world there would be an extra M.2 slot here to fill the empty void, or a larger fan and greater fin surface area to decrease the noise when running at its rated 25W TDP.

Looking at it the other way, if there was a hypothetical laptop that was much thinner than this it would have to forgo either cooling or battery. The ancient Asus Zenbook UX305 models used 5-Watt passively cooled Core M CPUs and therefore the battery fit in the thicker end of the tapered chassis where cooling and heatpipes would go in a modern machine. They were basically as thin as the touchpad at the thin end and behind the touchpad there was nothing at all just useless space that was too thin for anything at all but had to be there as a palm rest and to make the laptop deck as long as the screen was tall. As portable as those things were, they were underwhelming in real-world use, fragile, and we retired our whole fleet of those earlier than expected due to lack of upgradeability and low, fully-soldered specs that prevented us from buying higher spec when new.

Yes, but you only have two slots. The new format allows a laptop to have an expendability of 4 slots.

 

[TheLostSwede]

So it's basically LGA for Memory then

Not quite, even though it's somewhat similar.
This is the current bridge connectors that Dell is already using in some of their products, but in multiple sets to connect graphics cards.
Below that is a card with three sets of pads, which is what the CAMMs will have. Note that the graphics card was made in 2018, so this is not something new for Dell.
It's not nearly as complex or as easily damaged as LGA sockets.

 

[Valantar]

This is what I'm saying, that's a lie presented to you by manufacturers for why they solder the RAM onto the board. They do it because it's a cost-saving for them, and they can force/persuade buyers into CPU/Screen/SSD upgrades they weren't necessarily interested it by segmenting the larger RAM capacities to those upgraded SKUs. Sadly it's an incredibly anti-consumer practice that has been obscured by easily disproven claims that it's for reducing the height.

I have one of the thinnest 15" laptops on the market, an Envy X360 and it has two SODIMM slots:

View attachment 245078
View attachment 245079

Even with an EMI shield over the top, and it being directly under the keyboard deck, The SODIMM slots are still not the limiting factor in the laptop's thickness:

• The speakers and the battery are both each as tall as the keyboard, motherboard, SODIMMS and EMI shield combined
• The keyboard deck actually flexes a little on the right because there's no RAM behind like on the left side to fill the void between the fans and the battery.
• The rear exhausts for the two fans are laughably thin slits because the laptop is no taller than a USB-A and HDMI port at it's thickest point. Even with two fans, this thing is very audible at just 25W cTDP and it spends most of its time at 15W because that's all the fans can handle quietly.

This thing is entirely limited by the thickness of the battery at the front and the already-far-too-slim cooling system at the back. There's loads of empty space in the middle for chunkier components and absolutely no advantage to replacing the SODIMMs with something thinner; All that would do is increase the keyboard flex. I guess in an ideal world there would be an extra M.2 slot here to fill the empty void, or a larger fan and greater fin surface area to decrease the noise when running at its rated 25W TDP.

Looking at it the other way, if there was a hypothetical laptop that was much thinner than this it would have to forgo either cooling or battery. The ancient Asus Zenbook UX305 models used 5-Watt passively cooled Core M CPUs and therefore the battery fit in the thicker end of the tapered chassis where cooling and heatpipes would go in a modern machine. They were basically as thin as the touchpad at the thin end and behind the touchpad there was nothing at all just useless space that was too thin for anything at all but had to be there as a palm rest and to make the laptop deck as long as the screen was tall. As portable as those things were, they were underwhelming in real-world use, fragile, and we retired our whole fleet of those earlier than expected due to lack of upgradeability and low, fully-soldered specs that prevented us from buying higher spec when new.

Okay, so, here's the thing: something being difficult does not make it impossible, and connected to this; something being possible does not make it easy. And something being possible does not make it well suited to the task. I've never said that no thin-and-light design can fit SO-DIMMs; I've said that most can't, especially in the 13" class. And no, this isn't a marketing lie, it's an easily proven fact. Heck, your own laptop demonstrates it - look at the massive area taken up by those DIMMs! And that's in a 15" chassis - even if yours does seem to have a ton of barely utilized board space on the left, there's no way that would fit into a 13" chassis unless you also make it thicker, using smaller footprint, taller components stacked more densely.

And that's part of the thing: that being a 15" device inherently makes it easier to make it thin, through allowing for the use of wider, lower profile components (chokes, batteries, fans, etc.). That yours seems to use its SO-DIMMs as a structural component just supports this - apparently there's zero clearance there! So, for example, a thinner memory module could then allow for a better supported bottom plate design with more rigidity. Or it could allow for a larger battery than that relatively paltry 51Wh unit. Or it could allow for the second fan to be the same size as the first.

(Also, it's rather odd for you to seemingly use the structural support offered by the DIMMs as some kind of pro here - that's clearly a poor casing design, neither more nor less, and using a more space efficient memory type wouldn't affect that in either direction. That the laptop does overall seem to have some very odd priorities made in its design - such as that tiny secondary fan - speaks more to a poor overall design than this somehow being related to its use of SO-DIMMs. Also, it's often cheaper to stick a pair of SO-DIMM slots on a board than to design trace routing for a soldered memory layout. Off-the-shelf, high volume components are very cheap.)

(You're also misrepresenting some things a bit here: your battery is stacked with the touchpad, so it's only partially full thickness, and the speakers live in the tapered portion of the chassis, mostly being far thinner than the middle. The chassis also seems to have an overall wedge shape, being slightly thinner at the front, but that might just be an optical illusion from the tapered front edges. But regardless of this, both batteries and speakers can be shaped quite freely to fit whatever space is available. SO-DIMMs can't.)

Heck, you have 13" devices with SO-DIMMs too, like the Framework laptop, but in that you can again see just how ludicrous the board space requirement for dual SO-DIMMs is for such a small device. (And it's greatly helped by using a 3:2 display, giving it just that tad extra area to work with.) That doesn't mean it can't be done, but it comes with severe drawbacks, and it has a strong deterministic effect on the possible design variations. A more spatially efficient design will change those effects, giving more design flexibility.

After all, as that CAMM-to-SO-DIMM carrier board shows us, the CAMMs are barely wider than a SO-DIMM, yet they are inherently dual channel - and they don't need to be as deep (long?) as the full sized designs. Unless you're designing for a memory capacity of 64GB or more (which isn't necessary for the vast majority of consumer products), you can design for the smallest CAMM size, which is barely larger than a single SO-DIMM in X and Y, while being lower in Z.

Just to be clear (which IMO I have been, but apparently repetition is still needed): I have in no way argued for the creation of thinner laptops. I've argued that this can allow for more densely packed devices with more efficient internal layouts without sacrificing repairability and upgradeability. SO-DIMMs due to their size and Z-height have a strong determining effect on where they can be placed and how they fit, and even if they hang off a motherboard edge they require a lot of vertical clearance to fit as they're nowhere near in line with the motherboard. Doing the same with this CAMM would be far more spatially efficient, and allows for more flexible implementations overall. You can still make the design thicker if you want to, and if you do, you have more space for structural support, larger batteries, larger (or more) speakers, better keyboards, etc. Or you can go thin without needing to resort to soldered memory. This can allow for less compromised designs. And that's the important part. Sure, it can also be used for ludicrously thin, bad designs - but if that's the way an OEM wants to go, they can already do that with soldered RAM. There are no new disadvantages to this design outside of possibly cost and the time needed for standardization and adoption. But there are also plenty of advantages - OEMs just need to make use of them.

Here's another example: my work laptop, a Dell Latitude 7390 2-in-1. It's a pretty bad laptop in many regards, with poor cooling and a CPU configured to a mere 12W. It also has the smallest, thinnest fan I've ever seen (and it still vibrates and touches the casing at times!). Most of this is likely because Dell chose to give this laptop a pretty great keyboard (for its thickness), plus (like with yours) a thick, reinforced display for pen input.

Still, I'd like you to let me know how they could have fit upgradeable memory in here with SO-DIMMs. Because judging by the size of these CAMMs, they could have fit the smallest size of CAMM in here, under the RF shield where its soldered memory lives. (It's also worth noting that the Latitude has a bigger battery than your 15" device!). So: tradeoffs have been made. This is still not a very thin device, mostly thanks to the very thick display. But it's fine in terms of size. If CAMM could allow for designs like this (or ideally better executed ones) with upgradeable memory, that would be amazing.

Not quite, even though it's somewhat similar.
This is the current bridge connectors that Dell is already using in some of their products, but in multiple sets to connect graphics cards.
Below that is a card with three sets of pads, which is what the CAMMs will have. Note that the graphics card was made in 2018, so this is not something new for Dell.
It's not nearly as complex or as easily damaged as LGA sockets.

I really, really wish something like this could be adopted as an industry standard. That would be so great, on so many levels.

 

[TheLostSwede]

@Valantar another thing that would be interesting with the CAMM, is if it was possible to use with LPDDR types of memory, as these are always soldered today.

Also, my old 12.5" Thinkpad X250 has a SO-DIMM slot and it has two batteries as well...
Personally I still think we need to move to a better interface, if this is it or not, I don't know. However, at some point in time, progress is needed.

 

[wahdangun]

i think everyone miss the point, this thing beside being smaller and space efficient, its also dual channel and can support much more speed, and if this thing can prevent soldered ram, then I'm all for it, no more single channel ram.

 

[Valantar]

@Valantar another thing that would be interesting with the CAMM, is if it was possible to use with LPDDR types of memory, as these are always soldered today.

Also, my old 12.5" Thinkpad X250 has a SO-DIMM slot and it has two batteries as well...
Personally I still think we need to move to a better interface, if this is it or not, I don't know. However, at some point in time, progress is needed.

Yeah, that thought struck me too - if this can make for modular LPDDR, that would be fantastic. And yeah, we need new interfaces - across the board, really. Keeping compatibility is great (for PCIe and the like), but when you run into a wall, you run into a wall. And it's not like DIMMs are compatible across generations anyhow. Moving to a new interface more suited to the needs of upcoming designs and hardware standards is a necessity at this point - and argubably should have happened with DDR4, seeing how that was when soldered RAM seemed to take off too.

 

[Chrispy_]

i think everyone miss the point, this thing beside being smaller and space efficient, its also dual channel and can support much more speed, and if this thing can prevent soldered ram, then I'm all for it, no more single channel ram.

Yeah, the speed of SODIMMs is an issue that does need correcting. Timings on SODIMMs are awful compared to the same ICs on desktop DIMMS.

I have no problem with SODIMMs being universally superseded by something faster, but if CAMMs fragment the DDR6 market into conflicting standards, that's a terrible thing.

 

[trsttte]

Yeah, that thought struck me too - if this can make for modular LPDDR, that would be fantastic. And yeah, we need new interfaces - across the board, really. Keeping compatibility is great (for PCIe and the like), but when you run into a wall, you run into a wall. And it's not like DIMMs are compatible across generations anyhow. Moving to a new interface more suited to the needs of upcoming designs and hardware standards is a necessity at this point - and argubably should have happened with DDR4, seeing how that was when soldered RAM seemed to take off too.

The reason for soldering wasn't only space, also power savings (in the case of lpddr4) and the illusion of the supposed cold boot attack freezing memory modules to retain data. Depending on the situation it can also be cheaper to manufacture since soldered memory is placed by a machine with the rest of the components, modules need to be inserted manually. DDR4 moving to a new interface wouldn't necessarily change any of that (granted it could certainly help in avoiding it).

I have no problem with SODIMMs being universally superseded by something faster, but if CAMMs fragment the DDR6 market into conflicting standards, that's a terrible thing.

It's more likely to fragment DDR5, by DDR6 they must sort it out

 

[Valantar]

The reason for soldering wasn't only space, also power savings (in the case of lpddr4) and the illusion of the supposed cold boot attack freezing memory modules to retain data. Depending on the situation it can also be cheaper to manufacture since soldered memory is placed by a machine with the rest of the components, modules need to be inserted manually. DDR4 moving to a new interface wouldn't necessarily change any of that (granted it could certainly help in avoiding it).

Yup, all of those, but also AFAIK LPDDR4 and 4x can't handle the trace lengths and in-line connectors needed for SO-DIMMs, so soldering is the only option. My hope is that this can allow for the CAMM to be closer to the CPU (no need to space things out for matched trace lengths to two sockets), which might get within the requirements for LPDDR, plus the improved connector will no doubt have less resistance and other detrimental effects on the signal. Of course that freezing DIMMs thing is ... well, rather theoretical given the level of physical access you need for that to work - plus a screwed-in CAMM would likely make that very challenging to pull off in practice as the removal/installation procedure would take quite a lot longer, and you'd need to keep it frozen that whole time. But that's an extreme edge case either way. IMO the cost is a wash - one is cheaper in some situations, another in others, but the difference isn't likely to be huge either way. CAMM will no doubt be more expensive in the beginning, especially due to the rather unusual connector, but nothing that economies of scale can't fix - and trace routing to a single socket is likely slightly easier than to two SO-DIMM sockets.

 

[wahdangun]

Yeah, the speed of SODIMMs is an issue that does need correcting. Timings on SODIMMs are awful compared to the same ICs on desktop DIMMS.

I have no problem with SODIMMs being universally superseded by something faster, but if CAMMs fragment the DDR6 market into conflicting standards, that's a terrible thing.

it will be JEDEC standard so if some manufacture other than dell want to used it they can.

 

[Valantar]

it will be JEDEC standard so if some manufacture other than dell want to used it they can.

Saying "it will be" is rather premature. Dell reportedly wants it to be one, and there are good reasons for this or something similar to become a JEDEC standard, but JEDEC is an industry standards body, and no single actor can just come up with a new standard and then say "hey guys, this is the new standard". They can suggest it, and it will then go through the regular feedback and iteration process that such standards go through, likely involving feedback from all relevant/interested JEDEC members.

 

[noel_fs]

thats surprising unironically