Running the Zwift app on my fanless M2 MacBook Air is causing a significant amount of heat to build up and I’m worried if this could eventually damage the machine. Even with having the laptop up on a stand to allow for airflow underneath and sharing my desk fan I saw it reach 102°C. It had reached 90°C before I was even out of the warm-up (literally!) pen!
All of the answers on Quora and similar sites (It won’t let me add a link) suggest 100°C is way too high
I realise this machine is not built for sustained high-end performance but I believe there is supposed to be some kind of throttling in place to handle this and I wonder why it doesn’t seem to be working with Zwift?
I’ve seen suggestions that running on battery helps with this but it’s hardly ideal for a long indoor session to be paranoid about running out of battery.
When Zwift gets a native Apple Silicon build this should improve or go away. Your laptop has temp sensors everywhere and will throttle itself before it smokes. But it still might burn an Apple logo into your lap (aka “customer branding”. sorry.) On my M2 Pro Zwift is the only thing that makes the fan turn on, so yeah, it’s cookin along.
Given that this is an M2 which gets a different graphics profile than the M1, it’s quite possible that we’re looking at the reason why they have not increased the graphics profile for Macs. On the M1 we get a hamstrung High profile with no rider shadows - more like Basic. On the M2 we get something like a full Medium profile with rider shadows. In this case it looks like the High profile on M1 Macs may be actually less demanding than the Medium profile on M2 Macs. I run on a 2021 M1 MBP and the fan doesn’t come on. On a 2017 Intel MBP the fan is blasting. In an M2 Air there is no fan.
Confirming this behavior on my M2 MBA as well (10c, 8/512). I agree that Zwift could be made much more efficient in this regard. However, based on my own googling, it seems that the M1 and M2 chips are built to withstand >100C temps and will start thermal throttling at around 108-109C. I would assume that if those temps weren’t safe, then it would throttle at a much lower temp, right?
I hate to be the person on a forum thread saying “the problem you’re having is not a problem, actually,” because it clearly is for you, and I want to recognize that. And the solution for you will be some combination of buying a laptop cooler and just kind of hoping Zwift will better optimize the code for Apple Silicon. But it seems that >100C cpu temperatures are well within safe normals for the M1/M2, crazy as that sounds to me. We can take some (literal) comfort in the fact that the laptop exterior does not reach that temperature, and only gets up to about 45C (112F) at max load, so you’re not going to fry an egg on your keyboard, set your desk on fire, or grill your lap.
If I’m reading the tech specs correctly: the Macbook Pro has a discreet GPU, where the Macbook Air doesn’t.
I’d imagine the lack of a GPU is a big reason OP’s system is struggling.
The M2 GPU is rated at just 3.6 teraflops. That’s less than half as fast as the RX 6600 and RTX 3050, and also lands below AMD’s much maligned RX 6500 XT (5.8 teraflops and 144 GB/s of bandwidth). It’s not the end of the world for gaming, but we don’t expect the M2 GPU to power through 1080p at maxed out settings and 60 fps.
It’s a feature of AppleSilicon that the GPU-Cores are on the same Die as the CPU-Cores and it’s also a feature that the RAM is on the same package.
Although the M2 runs a bit hotter than the M1, I get my personal M2 Air never near the regions I get into with my M1 MBP which does a lot of Swift, ObjC and C compiling. On my M2 I do, codingwise, mainly pure Swift.
But as both machines can easily run lot’s of graphic rendering in games without getting hot I doubt that Zwift will require that much power. On a pure graphical level, Zwift plays more in the lower regions and not where AAA-Titles are.
I belive the reason why Zwift is so demanding on AppleSilicon has much todo with the fact that it does not run natively there. So it has to run via Rosetta, which translates everything. And pretty likewise Zwift is using some Software-Layer to translate their 3D-Engine to Metal. I don’t know if Zwift is using DirectX, OGL or Vulcan on Windows but they can’t for sure not use Metal there … so they have to cast it in one way or another … which again requires a good amount of performance. All added up leads to more performance consumption on Apple Silicon.
The “easiest” way would be to bring Zwift native to Apple Silicon, but in such a large project “easy” could mean month of work.