Is the 70w usb-c charger actually compatible with the Mac mini 2024?

Does this mean it can be powered by usb-c or is it just a typo?
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That would be an interesting benefit. My monitor can provide 90W via TB4… I’d guess it’s a typo though. The Mini specs list Max continuous power at 155W. If you can power it from a 70W brick you’d be capping performance.

@Tilden
Does 155W include the power output of the 5 usb-c/thunderbolt ports?

@Tilden
Neither the M4 nor M4 Pro will take anywhere near 155W. The PSU rating has a lot of overhead: 1. You usually take it at 80% to allow for spikes or other anomalies plus efficiency, so that takes you down to 124W. You don’t need that for a usb-c charger so it’s 70W. 2. Each port needs to provide a certain amount of minimum power at 15W. So now that’s 49W. The M4 will mostly live around 15W and the M4 Pro will live under 30W. If you take away one usb plug used for the charger and don’t draw much on the others, you’d still be able to hit peak performance. But I agree it’s likely a mistake. I’m just pointing out that it’s possible it could work.

@Tilden
I have a laptop with a 140 watt power supply that does fine on the 90 watts my monitor can yield. As I understand it, performance does not increase linearly with power consumption, so that extra 50 watts ends up being a 10 - 15 percent boost.

@Vic
Your laptop has a battery to allow draw to exceed the power your monitor can deliver. A Mac Mini doesn’t.

Tilden said:
@Vic
Your laptop has a battery to allow draw to exceed the power your monitor can deliver. A Mac Mini doesn’t.

Could that be mitigated with a powerbank between the monitor and mini?

@Vic
Possibly, but you’re going to be hard-pressed to find anything that can deliver that level of power at a reasonable size and price. At a certain point, it becomes cheaper to buy a MBP. I’m guessing it was either a mistake, will force Low Power mode, or will disable power delivery to the output TB/USB C ports.

@Vic
You can mitigate it by just plugging your mac mini into an outlet… what are you doing with a power bank plus monitor power?

@Vic
I don’t think there are any powerbanks that would pass data from the mac to the monitor.

Gracen said:
@Vic
I don’t think there are any powerbanks that would pass data from the mac to the monitor.

That’s a good point, I don’t think any of them do USB pass-through or whatever you’d call that functionality.

@Tilden
Nah, I run my M2 Max Macbook Pro 16" off 60W most of the time, and it doesn’t ever discharge faster than it’s being charged. I use my laptop for heavy stuff as well that get the fans going.

Charlie said:
@Tilden
Nah, I run my M2 Max Macbook Pro 16" off 60W most of the time, and it doesn’t ever discharge faster than it’s being charged. I use my laptop for heavy stuff as well that get the fans going.

Again, the battery will buffer any short-term heavy draws. It’s not uncommon for laptops to come with chargers larger than they need under all but the most extreme circumstances. The Mac Mini has no battery. If you need 71W and the adapter can only provide 70W, you’re going to have a bad time. The Mac Mini’s spec sheet says max continuous power of 155W. You’re not drawing 155W out of a 70W brick.

@Tilden
That wasn’t what I was saying. I’m highly skeptical of it actually needing anywhere near an actual draw of 155W. The 155W is also before the AC to DC conversion, otherwise known as at the wall. So a 70W power brick needs to draw more than 70W AC at the wall to supply 70W DC.

@Charlie
Max continuous power implies that short draws can exceed that. There is no practical way that this thing is going to be powered by a 70W brick without throttling or disabling functionality. As to your AC/DC conversion point, that’s true on the 155W, but not at a less than 50% efficiency. Modern low wattage power supplies using GaN are around 95% efficient. Even if Apple cheaped out on the design and it’s only 90%, you’re still looking at 140W DC.

@Tilden
Even accounting for transient spikes though, 155W sounds very excessive for a Mac mini. These M4s are in iPad Pros, obviously they’ll be capped and not quite the full chip, but I just can’t see it jumping up that high.

@Charlie
The M4 is, but it’s the 9 core version. The Mini can also have the M4 Pro though and that’s likely where the draw comes from, that and power delivery to the ports for bus-powered external devices. High performance external SSDs could be 10-15W, some high-end webcams are in the same ballpark. AV capture devices are pretty high power as well so it’s possible Apple is building in 50-60W for peripherals that could be disabled if you run from a low power PSU.

@Charlie
… because it is? There’s what the mini needs to run itself, but it also can power external accessories.

@Tilden
Not a typo and quite cool actually. Now one less cable goes to the socket if you have a proper monitor with type-c power out.

@Tilden
The interesting thing is the 35W chargers aren’t listed to support the Mac mini, but all chargers 70W and above are. If it’s a mistake surely it should cover all chargers right?