--- title: "Chip support" description: "Monitoring works on every Apple Silicon Mac. Fan control is validated on one Mac and experimental everywhere else. A chip-by-chip overview and how to send a report from your own Mac." canonical: "https://www.snejda.cz/en/helios/compatibility" language: "en" --- # Chip support Monitoring works on every Apple Silicon Mac. Fan control is validated on one Mac and experimental everywhere else. A chip-by-chip overview and how to send a report from your own Mac. ## What applies to every Mac Helios runs on Apple Silicon Macs (arm64) with macOS 13 or later. Intel Macs are not supported. Each reading either shows what the Mac and macOS expose or is marked Unavailable: a missing sensor never stops Helios from starting and is never shown as zero. Fanless Macs are fully supported for monitoring, and Macs with two or three fans are shown fan by fan. ## Chip-by-chip overview Experimental means Helios has not been tested on that Mac: fan control is off until you turn it on yourself, and it runs within stricter limits (see below). Whether a Mac really works is learned from people who try it and send a report. | Chip family | Temperatures | Sensor map | Fan control | | --- | --- | --- | --- | | M4, M4 Pro, M4 Max | Yes | Checked on real hardware (M4) | Validated on Mac16,1 with macOS 26 (build 25G83). Every other M4 model or macOS build: experimental | | M1, M1 Pro, M1 Max, M1 Ultra | Yes | From catalogue, confirmed per Mac at run time | Experimental | | M2, M2 Pro, M2 Max, M2 Ultra | Yes | From catalogue, confirmed per Mac at run time | Experimental | | M3, M3 Pro, M3 Max, M3 Ultra | Yes | From catalogue, confirmed per Mac at run time | Experimental | | M5 (and Pro, Max) | Yes; efficiency cores unknown on the base M5 | From catalogue, confirmed per Mac at run time | Experimental | | M6 | Yes | From catalogue (one source only) | Experimental | | A18 Pro (MacBook Neo) | Yes | From catalogue | Experimental if it has a fan | | Any Mac without a fan (MacBook Air) | Yes | As above | Not applicable | | Unknown or future chips | Shown as unclassified | None | Unsupported until a map exists | ## Temperature sensor maps Apple does not document which SMC keys hold which temperatures. Helios carries one key list per chip family, compiled from public sources and cross-checked against each other; a key the sources disagree on is left out. The same key can mean different things on different chips, so keys are matched to the detected chip only. Each map has a visible status in Thermals and the popovers: - Confirmed on this Mac: Helios watched the sensors follow the load of their own part of the chip (performance cores, efficiency cores, GPU) during normal use. Calibrate on the Thermals page speeds this up with a 40-second load. - Validated for this chip: the map checked on real hardware (the M4 family). - From catalogue, may be inaccurate: not confirmed yet. - Does not match this Mac: the sensors followed a different part of the chip, so Helios does not rely on them. ## What Helios does with unconfirmed temperatures Temperatures from a map that is neither confirmed nor validated are shown, but they never raise temperature alerts and never drive automatic fan control. ## Fan control Off by default on every Mac. Fan writes are pinned to the exact validated profile: Mac16,1 with macOS build 25G83. Every other Mac stays read-only unless its owner opts in to the experimental layer for that exact model and macOS build and its fan test passes. A read-only check first classifies the Mac as Validated, Experimental or Unsupported (for example when the Mac has no fans, Helios has no sensor map for the chip, or another fan controller seems to be running). - Helper: a small, fan-only program that macOS asks you to approve (Settings › Cooling). - Consent: Settings › Cooling shows what this Mac is and asks you to confirm three plain sentences: it is experimental, macOS stays in control and Helios only adds cooling, and temperatures on this Mac may be inaccurate. The consent covers the exact Mac model and macOS build; after a macOS update Helios asks again. - Fan test (experimental Macs): Helios holds each fan at its lowest factory speed for 20 seconds, checks that the Mac obeys, and hands the fans back to macOS. If the Mac does not obey, fan control stays off for that model and build. If the Mac is hotter than 85 °C or macOS does not hand over the fans at that moment, the test stops without a verdict and can be run again. - Automatic mode needs the performance-core sensors confirmed on this Mac first (or the validated M4 map). ## Fan control limits On the validated Mac the speed limit is 90 % of the factory maximum (it can be unlocked) and Boost is available. On an experimental Mac the limit is fixed at 70 % of the factory maximum and there is no Boost. On every Mac, Helios never runs the fans slower than macOS would: it takes them only when you ask for more cooling than macOS is giving, and above the speed limit it hands them back to macOS, which may use full speed. Control returns to macOS on any error, when the app stops responding, before sleep, when Helios quits and when the helper restarts; after a crash the helper restores macOS control when it starts. At 95 °C the helper acts on its own and cools as hard as it is allowed to, or returns the fans to macOS. Battery charging is never controlled; the helper has no battery code at all. ## What has been physically tested Fan control has been physically tested on one Mac: a 14-inch MacBook Pro with M4 (Mac16,1), on macOS 26 (25G83) and macOS 27.0.1 (26A434), at the factory minimum and above, with every return to macOS verified by reading the fans back. Everything else in the overview is experimental by design. ## Show Helios your Mac Fill in the form on GitHub: chip, macOS version, sensor map status and, if you tried it, the fan test result. Macs with a chip other than M4, Macs with two fans and desktop Macs are especially welcome. Thermals › All sensors also has Export SMC Dump…, which saves an anonymous list of the Mac's sensor keys to a file you can attach to the report; nothing is sent. Settings › Privacy & Diagnostics can also turn on a weekly compatibility report (off by default), and you can read its exact content before anything is sent. - [Send a report from your Mac](https://github.com/Snejdik/helios/issues/new?template=compatibility_report.yml) - [Full compatibility notes on GitHub](https://github.com/Snejdik/helios/blob/main/docs/APPLE_SILICON_COMPATIBILITY.md) --- HTML version: https://www.snejda.cz/en/helios/compatibility Other language: https://www.snejda.cz/helios/compatibility Overview for agents: https://www.snejda.cz/llms.txt