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16" MacBook Pro Battery Draining Faster Than Charger Can Replenish.
- Thread starter Xenden
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FYI I had this same issue and the problem turned out to be crappy third party (or maybe counterfeit) cables. My Apple brand cable (doesn't have to be the super expensive Thunderbolt 3, just the regular Apple USB charging cable) delivers 94w while the third party USB-C cables that came with an 87w power supply only deliver 60w. Change your cables and see whether that helps.
Sounds like a power delivery issue. I was using a MacBook Pro to drive a 4K display all while being plugged into a MacBook Air power supply and the battery was significantly lower when I stopped doing it.
It is part of the USB-C spec. A cable capable of handling Power Delivery of 100W (20V @ 5A) should to have the certification chip installed. Without this the cable will be limited to 60W (20V @ 3A) of power.
For what it is worth, I have a SurfaceBook that does the same thing. With the stock SurfaceBook charger from Microsoft, doing graphic design work all day will drain the battery even if plugged in. It is a small drain - it might be at 80% after a long day, so it has never been an issue for me. But it is annoying, and there are reports from gamers that their SurfaceBooks will completely die if they game for a long period of time.
This is 100% my experience. I was digging around trying to figure out an answer. Found that only 60w was being delivered to the computer under heavy load. It began to throttle around 4-5% and never would bounce over to using more than 60w of the 96w available. Tried 3 cables, 2 Belkin and one I received from a Google device and no luck, when I dug out the one that came with the box it has a noticeable thickness and immediately started delivering 94w to my struggling computer. Please ensure your connections are solid, this was the problem for me. Having the cheaper Belkin cable will work when on the go if I need, but now I notice that in multiple cases the Apple charger is superior (quicker charge) and a necessity for using the machine as a desktop replacement. I will say that I have been using the same Belkin cable to my Macbooks for years and haven't had this issue (never looked at power output, just never had as much drain) only until I now have the 16" model am I encountering this issue.
Basically there's two types of cables. Normal USB-C cables and things like dongles are only required to support 3 A. 3 A * 20 V = 60 W max.
Special USB-C cables, with thicker power wires and a e-marker chip, will support 5 A. 5 A * 20 V = 100 W max. Therefore, you need a cable that is advertised as supporting 5 A or 100 W charging.
This has been a requirement on all 15-inch+ USB-C Macs, since the first generation drew 87 W.
Special USB-C cables, with thicker power wires and a e-marker chip, will support 5 A. 5 A * 20 V = 100 W max. Therefore, you need a cable that is advertised as supporting 5 A or 100 W charging.
This has been a requirement on all 15-inch+ USB-C Macs, since the first generation drew 87 W.
I just ordered two USB-C cables with these characteristics.
- 100W (20V 5A)
- 10Gbps (~1GB/s)
- 2 meters (6 feet)
- Not Thunderbolt 3
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Same thing here playing Jedi: Fallen Order on Bootcamp on a base model 16” MacBook Pro.
I’m using only the original accessories (cable and charger) and the battery will drain under that game’s heavy load at about 5-10% an hour. I’m not massively worried as I don’t play for hours on end anyway, but I can’t imagine this being good for the battery, unless of course the machine is using two power sources (charger and battery) as opposed to charging and using up the battery simultaneously.
I’m using only the original accessories (cable and charger) and the battery will drain under that game’s heavy load at about 5-10% an hour. I’m not massively worried as I don’t play for hours on end anyway, but I can’t imagine this being good for the battery, unless of course the machine is using two power sources (charger and battery) as opposed to charging and using up the battery simultaneously.
On top of what others have already said, I would also add that your battery modules might be getting charged at a lower rate for being exposed to higher than “normal” temperatures when your MacBook is under full load. There may be a thermal limitation to ensure safe charging of the battery modules, hence reduced wattage when it is running warmer/under full load. I have noticed that trend when my MacBook is under full load/gaming/video editing/photo editing for an extended period of time but when I quit said applications and after my device cools down a little bit, charging seems to go back to normal.
Hope it helps. Cheers.
Hope it helps. Cheers.
That makes sense. I also wonder if Apple's stock USB-C charging cable support the 96W charger. I checked for specs everywhere and couldn't find evidence to support that and, presumably, it's the same cable that ships with all other MacBooks. It may be a case of the charging being bottlenecked by how much power the cable can deliver. It's curious that Apple specifies that its Thunderbolt 3 cable delivers over up to 100w, but makes no mention of what the situation is with the 2m USB-C cable... In any case I've already ordered a Satechi 100W cable because it's sturdier anyway.
Answer:
MBP16 Batt: 99Wh
Charger 96W
64 - 105 Watt GPU
https://www.notebookcheck.net/AMD-Radeon-Pro-5500M-GPU-Benchmarks-and-Specs.442754.0.html
35 - 45 Watt CPU
https://ark.intel.com/content/www/p...9880h-processor-16m-cache-up-to-4-80-ghz.html
MBP16 Batt: 99Wh
Charger 96W
64 - 105 Watt GPU
https://www.notebookcheck.net/AMD-Radeon-Pro-5500M-GPU-Benchmarks-and-Specs.442754.0.html
35 - 45 Watt CPU
https://ark.intel.com/content/www/p...9880h-processor-16m-cache-up-to-4-80-ghz.html
What is this answering? It would be bizarre if Apple aren’t supplying 100 W-capable chords with a 96 W power adapter!
How can I stress-test my Mac to check how much it can draw? I just downloaded iStat.
So I did a Cinebench test, and found something interesting and concerning.
According to iStat Menus, the "DC In" figure was just under 60 W, and it reported "Battery Current" at 42 W, for a "System Total" of 100 W.
If this is true, it means running the test indefinitely should drain the battery quite quickly; as some people seem to be reporting. I'm astonished if Apple has done this. It reeks of the cost-cutting and experience-cutting we saw in the 2016-19 MacBook Pros. This should get widespread coverage.
Has anyone replicated this and found a cable that delivers 96 Watts? If so, I'll be making a claim for Apple to cover the cost of such a cable.
I'm trying not to jump to conclusions, but I fail to see why iStat Menus would be wrong, unless I'm reading it wrong.
According to iStat Menus, the "DC In" figure was just under 60 W, and it reported "Battery Current" at 42 W, for a "System Total" of 100 W.
If this is true, it means running the test indefinitely should drain the battery quite quickly; as some people seem to be reporting. I'm astonished if Apple has done this. It reeks of the cost-cutting and experience-cutting we saw in the 2016-19 MacBook Pros. This should get widespread coverage.
Has anyone replicated this and found a cable that delivers 96 Watts? If so, I'll be making a claim for Apple to cover the cost of such a cable.
I'm trying not to jump to conclusions, but I fail to see why iStat Menus would be wrong, unless I'm reading it wrong.
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The included cable /definitely/ does the rated capacity of charger, if it isn't for you, then that needs to be investigated if somehow managed to swap an older cable or something? As earlier apple usb c cables I believe were limited to 60w, but all cables since the 87W+ chargers came out should be 100W capable.
Currently using a 87W charger and included cable:
Currently using a 87W charger and included cable:
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There is nothing wrong with this (assuming it's a momentary snapshot and not max what you are getting in). The power controller will balance stuff up and down to preserve battery health — especially if the battery is so close to its maximal charge.
It won't drain the battery unless your are using wrong chargers or your machine is defective. Try it out.
What reeks is the fact that they sell charging cable separately. Everything else is working as it should.
Cables that deliver 100W are included with your Mac. And no, I have never came across a new MBP that would discharge its battery under heavy load when plugged in — and I have tested dozens and dozens of them.
Yes, I posted a bit too early. I was able to draw > 90 W plugged into the right side. However, if that isn't possible on the left side, that is news to me. I don't recall Apple publicising that only certain Thunderbolt ports can function at full power.
I would say from the screenshot that it looks like either a 60w charger or cable is plugged in.
[automerge]1591268671[/automerge]
OK, that does indicate a possible fault or issue somewhere then, as all ports should be able to do full draw, and indeed do on my 16" certainly.
That would also indicate it probably is laptop at issue not the cable, contrary to other statements made.
"Has anyone replicated this and found a cable that delivers 96 Watts? If so, I'll be making a claim for Apple to cover the cost of such a cable."
is contraditected by you stating on right side ports you got over 90W...
It was not a momentary snapshot. The test takes a few minutes and it was very consistent during the test. Further, if it is normal to try and balance DC-In and battery power, that doesn't explain why it decided to (consistently) draw > 90 W from another port.
And the fact it can from another port indicates the cable is not the issue, and that there is an issue.
Try an SMC reset, it could be something glitching in the negotiation.
I've not been able to replicate it again. Who knows. You might be right about it "wanting" to draw a little bit of battery power.
So I'm not worried. The cable and power adapter are obviously fine, and I've not had problems with excessive battery drain. I think "Dr. MacRumors" has fuelled my anxiety in this instance.
Thanks for your help.
I suspect (as others have reported in this thread) that there was an issue with the Mac incorrectly recognising the power supply as a 60 W power supply or the cable as not rated at 100 W.
Before I ran the test, I was surprised and concerned to see that iStat Menus reporter it as such. I’ve since discovered this is not a permanent issue, but I’m unsure how or what triggered it.
I’ll certainly keep an eye out for it. Hopefully it was a rare issue. It was wrong for Apple to tell people that a maximum of 60 Watts power draw from the adapter is normal behaviour.
Just wanted to point out that I’ve encountered this “bug?” with the supplied power supply and USB-C cable.
Before I ran the test, I was surprised and concerned to see that iStat Menus reporter it as such. I’ve since discovered this is not a permanent issue, but I’m unsure how or what triggered it.
I’ll certainly keep an eye out for it. Hopefully it was a rare issue. It was wrong for Apple to tell people that a maximum of 60 Watts power draw from the adapter is normal behaviour.
Just wanted to point out that I’ve encountered this “bug?” with the supplied power supply and USB-C cable.
So I just came across this thread as I was at 2% battery while playing wow. I had my power cord into the AV Multiport Adapter. This was always dropping my battery while playing wow. I just looked at the system report as a previous poster suggested and noticed it said 55 watts. I took the power out of the Multiport and put it directly into a USB-C slot and now my unit is charging... it says 86 watts now, not sure if that's what it's supposed to say or not, but it's charging with wow blaring...
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