BootCamp Performance Control

BootCamp Performance Control (BCPC) is an open-source Windows utility for Intel Macs running Windows through Boot Camp.

Its goal is to reduce unnecessary heat and thermal throttling using conservative Windows processor power management and guarded Apple SMC fan control when a verified runtime capability family is present.

Download the latest stable release · Download 0.5.0-rc.2 · All releases and pre-releases · Hardware compatibility · Fan control · Changelog

Release status

• Current stable release: 0.4.0
• Current release candidate: 0.5.0-rc.2
• Stable status: 0.4.0 remains the recommended stable build and remains GitHub's latest stable release.
• RC status: 0.5.0-rc.2 is published as a GitHub pre-release for controlled compatibility testing.
• Current fan-control milestone: dynamic topology plus bounded PerFanModeFloat32 and GlobalMaskFpe2 capability-family writers.
• Physical fan-control validation: MacBookPro16,1 end-to-end for PerFanModeFloat32; MacBookPro12,1 one-fan write/readback/Apple Auto round trip PASS for GlobalMaskFpe2.

Previous published 0.5.0-rc.1 identity:

Tag:           v0.5.0-rc.1
Source commit: 27511afee7e1ae092bb53e63d8c1c96b73004c81
ZIP:           BootCampPerformanceControl-0.5.0-rc.1-win-x64.zip
ZIP size:      70320423 bytes
ZIP SHA-256:   B2215F7C6846614F2F1606A5DC11DC2D0BB1A496C66ACBA523B607A8DC65DDD5
Tests:         589 / 589 PASS

The annotated release tag is immutable project evidence for that previous candidate. Documentation and development commits made after publication do not move or rewrite v0.5.0-rc.1.

Published 0.5.0-rc.2 identity:

Tag:           v0.5.0-rc.2
Source commit: 59450231ef06db4ffdb86302855c4394f1bda6ba
ZIP:           BootCampPerformanceControl-0.5.0-rc.2-win-x64.zip
ZIP size:      70340224 bytes
ZIP SHA-256:   573F5E36BEB0D4DB98CBAFCFAD3634B003955F7719F1499CFA504D5B708A5F88
.NET SDK:      8.0.424
Tests:         632 / 632 PASS

The annotated v0.5.0-rc.2 tag and published ZIP are immutable release evidence. Post-release documentation commits on main do not move the tag or replace the published artifact.

0.5.0-rc.2 determines normal SupportedIntelMac eligibility from Apple hardware plus an Intel CPU and gates fan writes separately through a strict live SMC capability-family match. Exact model identity is not normal writer permission, and physical evidence for one machine is not a model whitelist.

Important: Gaming Optimised uses Maximum Processor State 95% / 95% and disables Turbo/Boost on AC and DC for every SupportedIntelMac. Fan control is additive and remains independently capability-gated.

Quick start

For normal use, start with the latest stable release. For 0.5.0-rc.2 testing, use the dedicated 0.5.0-rc.2 GitHub pre-release.

1. Download the matching win-x64 ZIP and .sha256 file.
2. Optionally verify the ZIP SHA-256.
3. Extract the ZIP to a normal user-writable folder.
4. Run BootCampPerformanceControl.exe.
5. Review the detected Mac model and current processor/fan state before applying any profile.

For the AppleSMC compatibility backend, BCPC currently interoperates with a separately installed Windows copy of Macs Fan Control 1.5.16. BCPC does not bundle Macs Fan Control, AppleSMC, or any third-party driver.

What BCPC does

Gaming Optimised

On every SupportedIntelMac:

• Maximum Processor State AC/DC: 95% / 95%
• Intel processor boost (PERFBOOSTMODE) AC/DC: Disabled / Disabled
• Display settings: unchanged

Fan control is additive:

• if the live AppleSMC backend matches an exact bounded capability family and all ownership/safety checks pass, Gaming Optimised also applies Maximum Safe RPM to every discovered fan using fresh live F{i}Mx values;
• if AppleSMC is missing, stopped, unsupported, reports FNum = 0, or the fans are already Manual without BCPC ownership, Gaming Optimised remains available as a CPU-only profile;
• if fan state becomes ambiguous after BCPC has started hardware writes, the recovery context is retained and the operation fails closed rather than guessing.

MacBookPro16,1 has completed BCPC end-to-end physical write validation for the PerFanModeFloat32 family. MacBookPro12,1 has completed the controlled one-fan GlobalMaskFpe2 Maximum Safe RPM / Apple Auto write/readback round trip. Runtime permission is never granted by either model identifier, and the two-fan GlobalMaskFpe2 path remains without BCPC-owned physical write qualification.

Restore Original Settings

BCPC restores the actual processor state captured before the profile was applied. It does not assume that the previous values were 100% or Windows defaults.

If BCPC currently has fan ownership/recovery context, Restore returns the owned fans to verified Apple Auto before restoring the saved Windows processor state. Without BCPC fan ownership, Restore does not invent fan work and restores the processor snapshot only.

Fan monitoring and recovery

When the AppleSMC backend can be safely read, BCPC can:

• discover the live fan count dynamically,
• read per-fan current RPM, maximum RPM, target and mode,
• report Apple Auto / Manual state,
• distinguish read capability from write eligibility,
• apply Maximum Safe RPM only after the full family/safety gate succeeds,
• persist fan-override ownership before the first hardware write,
• recover owned fans to Apple Auto after an unexpected BCPC process termination,
• leave the saved processor profile untouched during startup fan recovery so the user can explicitly choose Restore.

Hardware compatibility

Physically verified end-to-end

MacBookPro16,1 — MacBook Pro 16-inch (2019), Apple T2

Physical validation includes:

• Windows processor Apply / exact read-back / Restore,
• production fan monitoring and dynamic topology discovery,
• Maximum Safe RPM apply and read-back,
• Apple Auto restore,
• forced-process-crash recovery,
• fan-only resume without replacing the original processor Restore snapshot,
• exact processor-state restoration after recovery.

Primary validation machine:

• Windows 10 Boot Camp
• Intel Core i9-9980HK
• AMD Radeon Pro 5500M

See 0.5.0-rc.1 Hardware Validation Record.

GlobalMaskFpe2 capability family

MacBookPro12,1 — one-fan physical write qualification reference

Physical evidence from MacBookPro12,1 confirms the fpe2 big-endian / 4 RPM encoding and the global FS! mode authority. On 2026-09-08, the controlled qualifier verified FS! 0000 -> 0001, exact fresh F0Mx 60DC -> F0Tg, and FS! 0001 -> 0000, with exact readback at every stage and final Apple Auto verification.

The writer and hard-crash recovery paths remain covered by fake/in-memory validation; physical hard-crash recovery for this family is still a separate validation boundary. The one-fan Maximum Safe RPM / Apple Auto round trip is physically qualified, while two-fan FS! = 0003 still requires its own physical qualification. Restore Apple Auto with the current BCPC version before downgrading to a version that predates GlobalMaskFpe2; older marker schemas cannot represent global-mask ownership safely.

See 0.5.0-rc.2 GlobalMaskFpe2 Hardware Validation Record.

Other Intel Macs

The processor Gaming profile is available on SupportedIntelMac systems. Fan-write eligibility is not granted merely because a machine is an Intel Mac or is believed to contain T2.

0.5.0-rc.2 determines SupportedIntelMac from Apple hardware plus an Intel CPU; the exact model identifier does not decide normal processor-profile eligibility. Fan writes separately require the fresh runtime AppleSMC fingerprint documented in Hardware Compatibility and Fan Control. Physical validation records are evidence for the observed capability mechanisms, not runtime permission lists.

Fan-control dependency: Macs Fan Control 1.5.16

BCPC does not include, redistribute, modify, mirror, or install Macs Fan Control or its AppleSMC driver.

The physically validated AppleSMC compatibility environment uses a separately installed Windows copy of:

• Macs Fan Control 1.5.16 (Build 693)
• AppleSMC driver file version observed in the validated environment: 1.0.7.0

Download and install that version from the official CrystalIDEA GitHub release:

• https://github.com/crystalidea/macs-fan-control/releases/tag/v1.5.16

Use the official Windows installer (macsfancontrol_setup.exe). Do not copy applesmc.sys manually.

After installation:

1. Close the Macs Fan Control application if it is running. The AppleSMC device is exclusive and BCPC will not forcibly take ownership from another controller.
2. Start BCPC normally.
3. Use Enable Fan Monitoring if the AppleSMC service is installed but stopped and you explicitly want to activate monitoring. This is the user action that may request elevation to start the service.
4. Review BCPC's reported monitoring state, family write state and fan mode before relying on fan control.

Gaming Optimised does not silently start AppleSMC. If the fan backend is unavailable or not safely ownable, the conservative CPU profile can still apply.

Other versions of Macs Fan Control may work, but they are not part of the currently physically validated interoperability environment.

See Fan Control and AppleSMC Compatibility Backend and Third-Party Software.

Safety model

BCPC follows fail-closed rules for hardware-affecting operations:

• read current state before writing,
• persist the original processor Restore snapshot before modification,
• verify expected current state before processor writes,
• re-read fan capability immediately before fan writes,
• require the exact verified runtime fan-family metadata rather than trusting a model name,
• distinguish a backend-confirmed missing key from a failed key read; only confirmed absence can satisfy a family fingerprint,
• derive fan targets from fresh live SMC maxima rather than hard-coded RPM values,
• reject non-finite, non-positive or implausibly high maximum RPM data,
• allow only bounded family-specific per-fan mode/target keys and the proven global FS! mode key,
• never expose arbitrary SMC writes, minimum-RPM controls or a manual fan-speed slider,
• verify hardware state after writes,
• attempt Apple Auto compensation if the processor phase fails after fan takeover,
• restore owned fans before processor settings,
• persist an exact pre-write baseline transaction journal before hardware writes and retain recovery context across crashes,
• never infer BCPC fan ownership from Manual mode alone,
• never auto-start AppleSMC merely because a stale recovery marker exists,
• preserve CPU-only Gaming when fan control is unavailable or safely declined,
• fail closed if fan state is ambiguous after writes begin.

BCPC does not perform CPU undervolting, CPU MSR writes, firmware modification, or display-timing modification in this release candidate.

Installation details

Release build

1. Download the win-x64 ZIP and accompanying .sha256 file from the BCPC GitHub Releases page.
2. Optionally verify the ZIP's SHA-256 against the accompanying .sha256 file.
3. Extract the ZIP to a normal user-writable folder.
4. Run BootCampPerformanceControl.exe.

For fan control, separately install the tested Macs Fan Control dependency described above. BCPC does not bundle Macs Fan Control, AppleSMC, or any third-party driver.

The published Windows x64 build is self-contained and includes the required .NET runtime files.

Administrator permissions

BCPC runs normally without blanket elevation. Windows requests administrator permission only for operations that require it, such as changing protected processor power settings or explicitly starting the AppleSMC compatibility service.

Build from source

Requirements:

• Windows x64
• .NET 8 SDK

Build:

dotnet build BootCampPerformanceControl.sln -c Release

Run tests:

dotnet test BootCampPerformanceControl.sln -c Release

Create the self-contained Windows x64 release package:

powershell -ExecutionPolicy Bypass -File scripts/publish-release.ps1

The publish script creates a versioned self-contained win-x64 directory, ZIP, and accompanying ZIP .sha256 file in artifacts.

Documentation

• Latest stable release
• 0.5.0-rc.2 pre-release
• All releases and pre-releases
• Hardware Compatibility
• Fan Control and AppleSMC Compatibility Backend
• 0.5.0-rc.1 Hardware Validation Record
• 0.5.0-rc.2 GlobalMaskFpe2 Hardware Validation Record
• Third-Party Software
• Security Policy
• Changelog

License

BootCamp Performance Control is licensed under the MIT License.

Third-party software is not covered by the BCPC MIT license. See THIRD_PARTY.md.

Disclaimer

BootCamp Performance Control is an independent open-source project by MK Universal Solutions LTD and is not affiliated with, endorsed by, or sponsored by Apple Inc., Microsoft Corporation, CrystalIDEA, or Macs Fan Control.

Apple, Mac, MacBook Pro, Boot Camp, Windows, Microsoft, Macs Fan Control, CrystalIDEA, and other product names are trademarks or registered trademarks of their respective owners.