A) For what purpose do we even need 400GB/s?
B) Can a Mac even utilise all that speed? No, it can't, not even in lab tests designed to utilise as much as possible. I posted a link with a lot of detail on this the other day.
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I feel like i'm alone to dislike M1/what is it good for (Merged Mega Thread)
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B) Can a Mac even utilise all that speed? No, it can't, not even in lab tests designed to utilise as much as possible. I posted a link with a lot of detail on this the other day.
"working with heavy data analysis I appreciate every ounce of memory bandwidth my 14” MBP can give me"
How much do you think it is giving you, if you had to hazard a guess?
Edit: Bonus question- For CPU bound tasks, is more bandwidth utilised by Apple's fastest chip (with soldered RAM) than by Intel's fast chips that have removable DDR5 modules?
How much do you think it is giving you, if you had to hazard a guess?
Edit: Bonus question- For CPU bound tasks, is more bandwidth utilised by Apple's fastest chip (with soldered RAM) than by Intel's fast chips that have removable DDR5 modules?
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After using an M1 MBP for over 1½ years now, and moving from a 2015 MBP, I agree with this 100%.
I'd still be using my 2015 MBP if it wasn't for the Battery swelling up so much that the logic board breaks. It's happened to me twice. The first time it was still covered (in my LAST month!) of AppleCare+ and then the second time I was told it'd be $650-$750 to repair. Figured it would just happen again if I got it fixed, and I couldn't be happier.
For my workloads, I'd imagine I'm using the full 200 GB/s of my MBP's bandwidth (I only have the M1 Pro, not the Max). From what I can remember in Anandtech's tests, the M1 Pro can only saturate ~210 GB/s with a single core but multithreaded tasks should be able to use more of it. Am I remembering wrong?
(EDIT: re-read the Anandtech review and they found it can use 102 GB/s on a single thread and up to 248 GB/s with multiple threads, so I was indeed remembering wrong. However, they also state: "From a single core perspective, meaning from a single software thread, things are quite impressive for the chip, as it’s able to stress the memory fabric to up to 102GB/s. This is extremely impressive and outperforms any other design in the industry by multiple factors", which suggests comparable Windows/Intel machines can't pull similar real-world bandwidth.)
As for why it's useful: imagine an EEG dataset, where you're taking 1000 samples per second across 32 channels for a 30-minute experimental session. The resulting array of data is going to be 32 * 1000 * 60 * 30 = 57.6 million 64-bit floats, which you need to process with various filters and algorithms to improve the signal-to-noise ratio prior to analysis. Now, consider that an average EEG experiment is going to have 20 to 40 participants with similarly large datasets, and you'll see why being able to see why that fast memory read/write has major practical advantages. Given that a lot of different workloads similarly benefit from processing big data quickly in RAM, I think it's an important performance advantage.
To your bonus question: for an Intel laptop versus my own M1 Pro, the Intel machine would need at least 4 RAM sockets (and DDR5) to match my MBP's bandwidth. Such laptops probably exist on the market, but not with any form factor or battery life that I'd be interested in given the space and energy costs for 4 sockets.
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We're in agreement in all of that, and you're referring to the same article at Anantech that I linked to: https://www.anandtech.com/show/17024/apple-m1-max-performance-review/2
Your usage case is somewhat uncommon, but I see for you why you'd want the maximum bandwidth possible. I just wanted to point out how people hoping to get the full 400GB/s were going to be disappointed. For most tasks, good DDR5 modules on an Intel system should provide sufficient bandwidth, and more would not provide a tangible improvement.
I imagine, in regards to repairability, you're at least in agreement that batteries shouldn't be an intentional nightmare to replace? That's not helping anyone but glue manufacturers
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Battery swelling is a nightmare, isn't it... Never had an Apple MacBook battery last long enough to do that to me yet, though. I usually experience the issue where the laptop starts turning itself off when it gets down to about 30% of power, and I realise it's time to replace. (Despite not having gone through nearly as many charge cycles as it should be capable of.)
One MacBook Air ate 4 batteries in 7 years, before it was retired for good. By retired, I mean the RAM died. Which was a shame as it was still good for my niece's word processing, as I'd recently replaced the keyboard and battery.
Yes, absolutely! Batteries are one of the few parts that reliably degrade over time, so it would be awful for long-term usability if they couldn't be replaced. I've replaced batteries on laptops and iPhones to get years of extra use from them. Thankfully the M1 Air and Pro still have user-serviceable batteries under their new self-service repair program (not as easy to swap out as my X220's battery but still doable), I would have certainly hesitated to buy one if they locked that down.We're in agreement in all of that, and you're referring to the same article at Anantech that I linked to: https://www.anandtech.com/show/17024/apple-m1-max-performance-review/2
Your usage case is somewhat unusual, but I see for you why you'd want the maximum bandwidth possible. I just wanted to point out how people hoping to get the full 400GB/s were going to be disappointed. For most tasks, good DDR5 modules on an Intel system should provide sufficient bandwidth, and more would not provide a tangible improvement.
I imagine, in regards to repairability, you're at least in agreement that batteries shouldn't be an intentional nightmare to replace? That's not helping anyone but glue manufacturers
Also, while my performance use-case certainly isn't the norm, the power efficiency benefits of soldered RAM are still an important factor for the average user. See Hector Martin (the Ashai Linux guy)'s post on this here:
Higher clocks at half the voltage means measurably better battery life. That's not the right trade-off for everyone, of course, but I think it's a trade-off that makes sense for a lot of users. The ability to go 20 hours between charges coming from my X220 and its aging battery have been mind-blowing. Not having to carry a charger with you at all times really changes how you can use a laptop!
EDIT: Regarding battery life, I *hope* that the relatively low heat output and power demands of the M1 family will mean less stress on batteries throughout their lifespans. Swelling batteries are no fun at all to deal with, the 5S at my partner's workplace that they used to play music literally tore itself apart from the inside because the battery tore the display and its cables right off the logic board.
My 2015 MBP:
Keyboard: no issues
Ports: All functional
Ram: No apparent issue
SSD: Fully working
Battery: Most Definitely needs replacing
Not bad for a laptop that's getting on 7 years of age...
Thanks for the link- I'll read it tonight. I tried to find another article I read recently, suggesting that super high bandwidth wasn't much use for most people, but it was probably sponsored by Microsoft and Intel
It would be interesting to know how much more power it would take to operate two sticks of DDR5 in an Apple system, instead of the soldered RAM in the SoC.
I'm loving the battery life of my MacBook Air, by the way. It's astonishing how it sips power, even when occupied with what would have been power drains on the older Intel Macs. Better battery life as a brilliant thing, that most people will really appreciate. Of course for desktop Macs many people probably wish they'd let the electricity and heat run wild if it gave them greater performance. It'll be interesting to see if the SoC design hits thermal limits much lower than traditional systems do, because with the GPU/CPU/RAM squashed into a tiny space it creates a real hotspot.
That's good going. It's still on its first battery?? If you keep it for another couple of years you'll have to let us know how it degrades...
(Of course I know that all laptops are used differently, and that a USB port subjected to 100x more inserts than another will wear out faster, and heavier typing will likely hurt a keyboard's longevity, etc...)
Similar for me on the 2014 MBP that I finally sent off to my niece recently. Everything working fine but I did have to replace the battery a couple of years ago.
that generation required replacing the whole top case unit. My understanding is on the newer MBPs the battery replacement is much more straightforward. Not necessarily user replaceable but replaceable at a service center. That is fine with my. I don't want to have to open up a laptop and start swapping parts. I was never that good at playing "Operation!". 🦴
Yes, they will. More efficient = less power draw. Less power draw = quieter/cooler and, the case of MacBook, longer lasting battery.
Also, those of us who bought a M1 Pro/Max system for RAM-intensive workloads will certainly notice. 🙂
Not everyone’s workflow involved long periods of waiting for big chunks of data to be processed in RAM (high-res photo editing, video editing, 3D modeling, heavy data analysis/modeling), but for the minority who do (and buy high-end models over their entry-level counterparts) I can assure you every second those extra DDR5 channels save us add up.
I agree this is true. Do we know how much battery we are saving, though? I can't find anything on it, at all. Even trying to compare regular DDR5 to LPDDR5 is very hard. If it's only saving 2-3% battery life, for example, that wouldn't be terribly significant.
Apple surely went this route for financial reasons- probably because it was simpler to design the SoC in the same style they made their A series chips, as well as how it excuses their crazy RAM pricing- but performance and energy efficiency both profit as a result, however small that gain may be.
Edit: I know Apple delayed going from LPDDR3 to DDR4 because DDR4 was more energy intensive. They managed to do it in the end, and DDR4 was thirstier than DDR5 is. A figure of an additional 10% of total system consumption was attributed to the DDR4 RAM vs the LPDDR3, the year before they hit the bullet.
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I think the only reason why Apple didn’t go to LPDDR4 is because Intel was VERY late in supporting LPDDR4 for the i9’s(one of those things that were supposed to be in Skylake and kept getting delayed).
Well, I can only speak from my own experience, both as a consumer, and as a technician that repaired PCs/Macs for a little while. I have ALWAYS wanted the option of upgradeability in my computing devices. A few times I have actually upgraded, CPUs, RAM, storage (HDDs, never an SSD too long ago LOL), Optical Drives, motherboards, sound cards, and most definitely video cards. I upgraded both RAM and HDDs in Macs over the years, but since the advent of the "Retina" Macs, I have not upgraded one since. Likewise, the last time I purchased an upgrade for one my PCs was in 2017, which was a Video Card (a GeForce GTX 1070 those that are interested) that I used in eGPU enclosure for my PC Laptop at the time. The last upgrades I did resulted in complete new PC purchases. Granted the last one (January of 2021), was only done because it was cheaper to buy a whole new PC, than just the GPU upgrade that I wanted. So, even thought I want the option to upgrade, the reality of it is, I very rarely do upgrades any more. Most of the time I purchase what I need plus a little extra, and use it until I need more, then replace the whole machine. What I cannot say for sure is, if I had the options over the past decade or so to upgrade my machines (both Mac and PC), that I would have. All I can say is I have not, and can't say that I miss it all too much.
It's fine until a "minor" thing like lack of RAM or storage starts eating away at you... and most of us have at one point or another not bought enough of one or both of them from Apple, because of the extortionate costs. But I'm like you- I used to upgrade everything and build my own PCs, but the last 4 years I haven't made one upgrade even on the PC side (not counting a case fan that I replaced- and improved upon- because it starting making an annoying noise). Would have liked to have saved my old MacBook Air when its RAM died, of course
Actually the Mac was the easiest windows machine to administer in my experience. In my job I use MacOS, Windows and variations on UNIX, so the Intel Macs suited me to the ground. Not sure what I feel about the new M1 Macs, but eventually compatibility issues with running VM's with other OS's will be ironed out for AS Macs or the Apple ecosystem will begin to wither for professional users.
They also look fancier and more professional- I've worked for companies that had us all using Windows on MacBooks, because of the image they gave when we were out of the office, while keeping us chained to Windows because of the archaic custom software they still used.
I'm also struggling to find good wattage comparisons between socketed DDR4/5 and soldered LPDDR4X/LPDDR5, but I believe that LPDDR runs at half the voltage. From what I understand it has to do with the electrical costs of maintaining signal integrity at high clock speeds across sockets and long logic board traces: the faster the RAM, the more power that involves. Here's Hector Martin again (my main source for low-level technical understanding of the M1, since he's spent so much time reverse-engineering the guts of the SoC), talking about the power costs of sockets:
and again, in a different thread:
I'm not a power efficiency expert, but from the sounds of those posts the effects on battery life would be more than a few percentage points. Hopefully someone here with more technical knowledge is willing to work out the actual numbers.
It is not an EV, and I didn't say it was hard.
I took a look under the hood and concluded that it was more involved than just disconnecting terminals and loosening a couple screws. I checked the manual, and determined the time I would spend doing it is worth more than the cost of opting to have someone else do it.
You implied it was the opposite of easy- you can see why I used the word hard. It's worrying that a manufacturer would make a humble battery change anything other than a piece of cake- unless my car was already in the garage for other work, it would take me longer to drive to a mechanic than do it myself. Of course if you're paying for someone to pay you a visit at home, all you're weighing up in the time consumed with phone calls and greeting the bloke when he arrives, which would probably still be more wasteful of my time than replacing the battery myself 😅😅
Edit: I used to like repairing cars for fun, before I moved to China and didn't even drive regularly any more... I loved working through some genuinely baffling challenges, where there was no guide to work from.
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Yeah, I think you got the right idea. One place to see this in action is in PC laptop reviews. They won’t provide a completely accurate picture, BUT during the years where Intel was forcing laptop vendors who needed to ship high memory capacity machines to use DDR instead of LPDDR, across the board you see the same complaint in the reviews… that the battery life year to year suffered greatly.
It’s one of those things I looked into at the time to get a feel for the difference between DDR and LPDDR in the systems PC vendors had to ship.
Of course I had it done during annual service, so the only additional time spent was adding “please also replace the battery” when handing over the keys. I wasted more time than that opening the hood and finding the manual.