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Effect of 32 GB memory on battery life
- Thread starter maccuser
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About 10%? I really don’t know. That’s just a wild guess since they simultaneously began offering 32GB of RAM and increased battery capacity by 10%. But my guess is likely wrong
The effect would be close to zero. A single RAM stick takes less than 3 watts of power, which is literally nothing compared to the CPU or the GPU.
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That's most likely to offset the more power hungry 6 and 9 core CPUs
I wasn't sure. Apple kept saying that they were holding off on 32GB of RAM while waiting for a low power ram solution to be supported and then went ahead and released the new MBP without it. So I didn't know what the actual impact was.
Edit: Was trying to find Schillers statement on it from 2016 "To put more than 16GB of fast RAM into a notebook design at this time would require a memory system that consumes much more power and wouldn't be efficient enough for a notebook."
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If you search reddit, there is a thread on this very topic. From what I read, a small no. of people are saying it's around 15 -20 min shorter battery life going from 16 to 32GB which I find to be significant imo. That's a difference b/w having to use the laptop 20 min longer as opposed to being dead and being forced to find a wall plug.
No.
The problem was not the use of 32GB, but the use of DDR4.
The lowered power LPDDR4 isn't supported by current CPUs, and its predecessor - LPDDR3 - supports only 16GB.
So moving to supported RAM of 32GB forced Apple to use DDR4, which is more wasteful no matter how much RAM is installed.
They did increase the battery capacity to somewhat compensate however. So in real terms, the effect on battery life should be negligible.
20 minutes on 10 hours is ~3%? I'd be amazed if someone was attentive enough to notice that.
It will have an effect, but not noticeable. If you need 32GB RAM then you should be fine with this, if you're just getting 32GB because you think you could use it one day, then you'll be suffering a slightly lower battery life due to this. It's a trade-off, people need to make up their own mind as to whether it's worth it for them.
Again, they did it not because 32GB need more than 16GB, but because of moving to DDR4 (which is used in 16GB MBPs too), and because of many other reasons (like the 6-core CPU which needs a lot of power, T2, etc.).
Nevertheless, there might be a minor difference in power consumption between DDR4 16 and 32, but as you wrote, it's negligible.
Yes, I was saying the move from LPDDR to DDR required more battery as one is 'Low Powered'. I wasn't suggesting 32GB uses more power than 16GB?
OK, so we are saying the same...
BTW, yesterday I ordered MBP with 32GB, but they have a loooong backlog here in orders of the new models...
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OK, so we are saying the same...
BTW, yesterday I order MBP with 32GB, but they have a loooong backlog here in orders of the new models...
Plenty around here...
Battery life is average on these devices. I’m not sure if it’s down to the 32gb of ram.
Running word and Spotify I’m getting around 5-7 hours. Once I drop illustrator and after effects it’s around 3.
I wouldn’t imagine that the extra 16gb of ram is munching up 4-5 hours of battery. My logic is that more power consumption = more heat generated, therefore it would be releasing massive amounts of heat. Which it just isn’t, the underside would be roasting!!
Nonetheless this machine is a beast, my render times are down from 6 hours to 1 compared to my 2016 13 i5 16gb. Now that’s enough to shout about. There’s those who shout about a 10% performance spike, this is something to have a party over.
If you need the extra ram go for it, I didn’t think I would be doing motion graphics 4K on my 2016, couple months ago I even started green screening 1080.
The machine just wasn’t there for it. If you’re in doubt I would go get the 32gb, unless if you’re always remotely working, a plug socket isn’t really more than 5 hours away from you.
Running word and Spotify I’m getting around 5-7 hours. Once I drop illustrator and after effects it’s around 3.
I wouldn’t imagine that the extra 16gb of ram is munching up 4-5 hours of battery. My logic is that more power consumption = more heat generated, therefore it would be releasing massive amounts of heat. Which it just isn’t, the underside would be roasting!!
Nonetheless this machine is a beast, my render times are down from 6 hours to 1 compared to my 2016 13 i5 16gb. Now that’s enough to shout about. There’s those who shout about a 10% performance spike, this is something to have a party over.
If you need the extra ram go for it, I didn’t think I would be doing motion graphics 4K on my 2016, couple months ago I even started green screening 1080.
The machine just wasn’t there for it. If you’re in doubt I would go get the 32gb, unless if you’re always remotely working, a plug socket isn’t really more than 5 hours away from you.
Go there and find it yourself. Shouldn't be difficult to find. They never said anything about getting 10 hours of use.
If you need 32GB (and nobody buys 32GB unless they need it, surely) then the impact of not having the 32GB would be more swapping (more SSD work), more CPU work for memory compression and management, and overall reduced performance. So although their might be a modest increase in battery consumption if the RAM is idle; if you need that space then the system’s workarounds for low memory would be FAR more taxing on the battery.
Have you seen some posts that communicated that people bought ram just in case, or because they like to have many chrome tabs open? I'd say the majority of people buying 32GB don't need it, its my unofficial, nothing to back up opinion based on what I see here.