FIELD GUIDESource-led reference
Port & Cable

P344 / PC internal / Connector

4-pin PWM PC fan connector / motherboard header

A four-contact PC cooling-fan connector provides an additional PWM-control position alongside power and fan-speed sensing in the documented configuration.

Also called 4-pin PC fan header PWM fan header four pin PWM fan

Four contacts identify a candidate PWM form; they do not prove a particular board header offers PWM mode or adequate power.

Look for

Check the board marking (CPU_FAN, SYS_FAN or similar) and fan plug guide, then verify the pin functions in the exact motherboard manual.

Claim inspection dates: 2026-10-09, 2026-10-13 · Independent review pending

4-pin PWM PC fan connector / motherboard header: three-quarter view. Computer-generated illustration, not a photograph.

Three-quarter view Computer-generated illustration with prior AI visual review. Not a photograph, measurement or compatibility check. Independent technical and rights review pending.

4-pin PWM PC fan connector / motherboard header: mating face. Computer-generated illustration, not a photograph.

Mating face Computer-generated illustration with prior AI visual review. Not a photograph, measurement or compatibility check. Independent technical and rights review pending.

4-pin PWM PC fan connector / motherboard header: fitted in place. Computer-generated illustration, not a photograph.

Fitted in place Computer-generated illustration with prior AI visual review. Not a photograph, measurement or compatibility check. Independent technical and rights review pending.

4-pin PWM PC fan connector / motherboard header: original recognition drawing, not to scale.

Recognition drawing Original schematic, not to scale. Drawing review pending.

Image inspection / P344

See the view. Check its scope.

1 registered view for this reference. Different part examples are not automatically mates; all remain not to scale and independently unapproved.

Four aligned contacts and a guide cue in the inspected board diagram. Original source-observed board-side contact-layout study; no housing specification, scale, pin functions or fit approval. (private workspace)

P344 / Source-observed physical study

4-pin PWM fan

MSI B550-A PRO CPU_FAN1 / PUMP_FAN1 / SYS_FAN1–6

Board-side plan layout, following the cited diagram orientation · Board header

Not to scale. Technical and rights review pending.

Inspect view & provenance (private workspace)

Matching notes / PC control / P344

Does every four-pin header supply PWM control?

FIELD NOTES 03

The number of positions is not the guarantee. Noctua describes a fourth control signal, while the motherboard documentation determines implementation.

SOURCE-SUPPORTED LEAD

What the evidence supports

An appropriately documented PWM fan and PWM-capable header establish a control-method lead.

INSUFFICIENT MATCHING EVIDENCE

What not to conclude

A three-pin connection does not establish the presence of the separate PWM control signal.

NOT ESTABLISHED

Keep this check open

Header mode, exact control implementation and fan limits require the product manuals.

Before you choose a part

  1. Confirm the fan’s control interface.
  2. Read the specific motherboard header’s supported modes.
  3. Do not infer an RGB function or an electrical limit from pin count.
Evidence for this decision · 3 source-scoped observations

C344A (private workspace) — Noctua distinguishes its four-pin PWM fan connection by a fourth control signal; three-pin motherboard connection may not provide PWM control.

Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval. S454 · S455

C344B (private workspace) — Motherboard documentation—not the number of header pins—determines whether its fourth position is implemented as PWM.

Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval. S454 · S455

C343B (private workspace) — Speed regulation for a three-pin fan depends on a motherboard supporting DC or voltage control; a four-pin header alone is not a speed-control guarantee.

Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval. S454

Manufacturer evidence is not an independent review, wiring assignment or hardware test.

REPAIR FIELD NOTES / Fans and compact power

First verify the exact manufacturer series

PWM fan wiring is not a generic four-wire harness

No. The Noctua four-pin PC PWM fan example includes a distinct PWM control function in addition to the fan’s normal connections. Neither a four-position shell nor wire colors certify the signal assignment of a different fan controller or accessory.

Avoid: Matching an apparently standard four-pin plastic shell is not a wiring validation.

Full source-scoped reading and three practical checks ↗
Qualitative distinction between Micro-Fit · 3.0 mm and Mini-Fit Jr. · 4.2 mm. Nominal pitch cannot validate a power harness. Not to scale, no pinout, no mating approval.
Micro-Fit / Mini-Fit — different Molex familiesNominal pitch cannot validate a power harness. Original conceptual evidence diagram only, not part-number geometry, a live-circuit test, or manufacturer-approved fit.

These notes add editorial context to the original canonical reference; they do not change its claim IDs or prove mating, wiring or polarity.

The useful distinction

Recognize it. Then verify it.

A four-contact PC cooling-fan connector provides an additional PWM-control position alongside power and fan-speed sensing in the documented configuration. [C344A]

Motherboard documentation—not the number of header pins—determines whether its fourth position is implemented as PWM. [C344B]

Noctua distinguishes the female fan-cable connector from male PCB headers and male cable connectors. [C344C]

Noctua’s PWM white paper covers 5V, 12V and 24V four-pin models unless otherwise stated. [C344D]

B550-A PRO lists Auto for CPU_FAN1, PWM for PUMP_FAN1 and DC for SYS_FAN1–6 as default modes. [C344E]

Source-scoped identification facts

Each value retains its exact example, role and measurement axis. Facts from different parts must not be combined into an invented component.

Documented examples; not a mating drawing or compatibility approval
Positions / cavity span4 (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Populated contacts4 (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Contact rows1 (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Contact pitch2.54 mm Contact mating centerline pitch (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Dimensions / axis3.5 mm PC tail length (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Connector roleVertical male PCB header (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Contact gender / arrangementmale (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Mountingcable (Claim C344C); board (Claim C344C); through-hole (Molex 470531000 (47053-1000))S592 · S854Source-scoped examples are separate; select the exact variant and measured axis. V142: named MSI B550-A PRO manual version 6.0 (2024/02) or explicitly identified Noctua family only. Role/recognition evidence, not generic wiring, safe mating, pinout approval, dimensions or installed-device certification. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Coupling / latchLock to mating part: yes (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Keying / polarizationPolarized to mating part: yes; keyed to mating part: no (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Shell / formunshrouded (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
ManufacturerMolex (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.
Exact part / implementation470531000 (Molex 470531000 (47053-1000))S854Source-scoped examples are separate; select the exact variant and measured axis. Molex 470531000 (47053-1000). Named primary-source example only. Identification facts do not certify mating, electrical compatibility, fabrication or powered use.

Not recorded: Nominal contacts, Series, Recorded markings, View convention. Unknown fields stay unknown; illustrations supply no measurements or pin assignments.

Recorded variant and source limits
  • Check the exact device manual before wiring or applying power.
  • MSI MAG B550 TOMAHAWK fan header in PWM mode: Header numbering per manual.
  • MSI MAG B550 TOMAHAWK fan header in DC mode (same header, BIOS-selected): Header numbering per manual.
  • GIGABYTE B550 AORUS ELITE (AX) CPU_FAN/SYS_FAN/CPU_OPT headers: Header numbering per manual.
  • MSI B550-A PRO fan headers, PWM mode: MSI p.38 board-header sketches as printed: pin 1 is leftmost in the horizontal sketch. Check selected BIOS mode. Cable rear orientation is not established.
  • MSI B550-A PRO four-position headers, DC mode: MSI p.38 board-header sketches as printed: pin 1 is leftmost in the horizontal sketch. Check selected BIOS mode. Cable rear orientation is not established.
  • Noctua NF-A8 PWM, 12 V: Product specification numbers the fan-cable contacts; white paper identifies a female cable and shows wire colors. A numeric mating-face versus rear-view drawing is not established.
Report a correction to these facts →

Bounded facts, visible unknowns

Specifications and limits

4-pin PWM PC fan connector / motherboard header facts and limitations
Documented extra functionFourth contact conveys PWM control on specified PWM fan variants [C344A]
Role and recognition scopeBoard header — MSI B550-A PRO CPU_FAN1 / PUMP_FAN1 / SYS_FAN1–6. Original qualitative study only; no wiring or fit approval. [C344C] [C344D] [C344E]
Mechanical dimensionsOnly manufacturer-described nominal family/footprint pitch is quoted in sourced text; no measured fabrication/tolerance drawing independently approved.
Engineering pinoutSource-checked engineering profile available; independent review pending. Open engineering profile →
Verified device listNot included. Check exact device and accessory documentation.
A boundary, not an omission to guess around.

Power off before working near the CPU cooler and prevent the fan blades from turning. Check the exact header mode: some four-pin headers regulate voltage instead of delivering PWM control. Verify fan power, connector engagement and the board’s fan-control setting before relying on it for cooling.

Before you connect

What to check

  1. Power off before working near the CPU cooler and prevent the fan blades from turning.
  2. Check the exact header mode: some four-pin headers regulate voltage instead of delivering PWM control.
  3. Verify fan power, connector engagement and the board’s fan-control setting before relying on it for cooling.
Trace a supported connection class →

Pins & wiring

Pinout

Choose the exact wiring. Pin numbers follow its stated view; a schematic does not establish physical positions. Check your exact device before wiring.

What the status labels mean
Confirmed
Recorded research passes agree within this variant; this is not independent human review or hardware validation.
Single source
Only one underlying document, or one pass, supports this assignment.
Device-specific
Supported for the named equipment or wiring only. Check your device’s manual.
Unverified
Missing or conflicting evidence. Do not wire from this row.
Not connected
The source explicitly says NC, no contact or no pin for this wiring.
Wiring variant

MSI MAG B550 TOMAHAWK fan header in PWM mode

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

Header numbering per manual.

  • P344 4-pin fan — **Agree** for comparable PWM and DC modes — Different MSI board manuals agree: PWM = ground/+12 V/sense/control; DC = ground/voltage control/sense/NC. A adds GIGABYTE; B adds the Noctua PWM white paper and NF-A8 PWM specification. B supplies fan-side manufacturer evidence that A lacked; the Intel fan standard itself remains unavailable.
  • The Intel specification (fan-side electrical requirements, PWM frequency, tach pulses) was not obtained from an Intel host; fan-side pinout is not verified from the standard. Only motherboard-header variants are verified.
4-pin PWM PC fan engineering referenceHeader numbering per manual.SCHEMATIC · physical positions unconfirmedNot to scale · check the named wiring and device manual1: Ground (device_specific)12: +12V (device_specific)23: Sense (device_specific)34: Speed Control Signal (device_specific)4powergrounddataConfigshieldNCUnknown
Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.
MSI MAG B550 TOMAHAWK fan header in PWM mode — source-scoped contact map
PinSignalWhat it doesStatus
1GroundGround reference and return.Device-specific
Sources
2+12VPower connection (+12V). Check the specified supply.Device-specific
Sources
3SenseControl, detection or configuration connection; check the source and device.Device-specific
Sources
4Speed Control SignalControl, detection or configuration connection; check the source and device.Device-specific
Sources
Sources (1)

MSI MAG B550 TOMAHAWK fan header in DC mode (same header, BIOS-selected)

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

Header numbering per manual.

  • P344 4-pin fan — **Agree** for comparable PWM and DC modes — Different MSI board manuals agree: PWM = ground/+12 V/sense/control; DC = ground/voltage control/sense/NC. A adds GIGABYTE; B adds the Noctua PWM white paper and NF-A8 PWM specification. B supplies fan-side manufacturer evidence that A lacked; the Intel fan standard itself remains unavailable.
  • Mode is selectable in BIOS; CPU_FAN1 defaults to Auto, PUMP_FAN1 to PWM, SYS_FAN1~6 to DC.
  • The Intel specification (fan-side electrical requirements, PWM frequency, tach pulses) was not obtained from an Intel host; fan-side pinout is not verified from the standard. Only motherboard-header variants are verified.
4-pin PWM PC fan engineering referenceHeader numbering per manual.SCHEMATIC · physical positions unconfirmedNot to scale · check the named wiring and device manual1: Ground (device_specific)12: Voltage Control (device_specific)23: Sense (device_specific)34: NC (not_connected)4powergrounddataConfigshieldNCUnknown
Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.
MSI MAG B550 TOMAHAWK fan header in DC mode (same header, BIOS-selected) — source-scoped contact map
PinSignalWhat it doesStatus
1GroundGround reference and return.Device-specific
Sources
2Voltage ControlControl, detection or configuration connection; check the source and device.Device-specific
Sources
3SenseControl, detection or configuration connection; check the source and device.Device-specific
Sources
4NCNot connected or absent in this named wiring.Not connected
Sources
Sources (1)

GIGABYTE B550 AORUS ELITE (AX) CPU_FAN/SYS_FAN/CPU_OPT headers

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

Header numbering per manual.

  • P344 4-pin fan — **Agree** for comparable PWM and DC modes — Different MSI board manuals agree: PWM = ground/+12 V/sense/control; DC = ground/voltage control/sense/NC. A adds GIGABYTE; B adds the Noctua PWM white paper and NF-A8 PWM specification. B supplies fan-side manufacturer evidence that A lacked; the Intel fan standard itself remains unavailable.
  • The Intel specification (fan-side electrical requirements, PWM frequency, tach pulses) was not obtained from an Intel host; fan-side pinout is not verified from the standard. Only motherboard-header variants are verified.
4-pin PWM PC fan engineering referenceHeader numbering per manual.SCHEMATIC · physical positions unconfirmedNot to scale · check the named wiring and device manual1: GND (device_specific)12: Voltage Speed Control (device_specific)23: Sense (device_specific)34: PWM Speed Control (device_specific)4powergrounddataConfigshieldNCUnknown
Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.
GIGABYTE B550 AORUS ELITE (AX) CPU_FAN/SYS_FAN/CPU_OPT headers — source-scoped contact map
PinSignalWhat it doesStatus
1GNDGround reference and return.Device-specific
Sources
2Voltage Speed ControlControl, detection or configuration connection; check the source and device.Device-specific
Sources
3SenseControl, detection or configuration connection; check the source and device.Device-specific
Sources
4PWM Speed ControlControl, detection or configuration connection; check the source and device.Device-specific
Sources
Sources (1)

MSI B550-A PRO fan headers, PWM mode

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

MSI p.38 board-header sketches as printed: pin 1 is leftmost in the horizontal sketch. Check selected BIOS mode. Cable rear orientation is not established.

  • P344 4-pin fan — **Agree** for comparable PWM and DC modes — Different MSI board manuals agree: PWM = ground/+12 V/sense/control; DC = ground/voltage control/sense/NC. A adds GIGABYTE; B adds the Noctua PWM white paper and NF-A8 PWM specification. B supplies fan-side manufacturer evidence that A lacked; the Intel fan standard itself remains unavailable.
  • Defaults: CPU_FAN1 Auto, PUMP_FAN1 PWM, SYS_FAN1–6 DC.
  • A four-pin shell does not identify voltage. Unexamined 5 V/24 V models, proprietary headers and cable-rear numbering remain unverified.
4-pin PWM PC fan engineering referenceMSI p.38 board-header sketches as printed: pin 1 is leftmost in the horizontal sketch. Check selected BIOS mode. Cable rear orientation is not established.SCHEMATIC · physical positions unconfirmedNot to scale · check the named wiring and device manual1: Ground (device_specific)12: +12V (device_specific)23: Sense (device_specific)34: Speed Control Signal (device_specific)4powergrounddataConfigshieldNCUnknown
Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.
MSI B550-A PRO fan headers, PWM mode — source-scoped contact map
PinSignalWhat it doesStatus
1GroundGround reference and return.Device-specific
Sources
2+12VPower connection (+12V). Check the specified supply.Device-specific
Sources
3SenseControl, detection or configuration connection; check the source and device.Device-specific
Sources
4Speed Control SignalControl, detection or configuration connection; check the source and device.Device-specific
Sources
Sources (1)

MSI B550-A PRO four-position headers, DC mode

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

MSI p.38 board-header sketches as printed: pin 1 is leftmost in the horizontal sketch. Check selected BIOS mode. Cable rear orientation is not established.

  • P344 4-pin fan — **Agree** for comparable PWM and DC modes — Different MSI board manuals agree: PWM = ground/+12 V/sense/control; DC = ground/voltage control/sense/NC. A adds GIGABYTE; B adds the Noctua PWM white paper and NF-A8 PWM specification. B supplies fan-side manufacturer evidence that A lacked; the Intel fan standard itself remains unavailable.
  • A four-pin shell does not identify voltage. Unexamined 5 V/24 V models, proprietary headers and cable-rear numbering remain unverified.
4-pin PWM PC fan engineering referenceMSI p.38 board-header sketches as printed: pin 1 is leftmost in the horizontal sketch. Check selected BIOS mode. Cable rear orientation is not established.SCHEMATIC · physical positions unconfirmedNot to scale · check the named wiring and device manual1: Ground (device_specific)12: Voltage Control (device_specific)23: Sense (device_specific)34: NC (not_connected)4powergrounddataConfigshieldNCUnknown
Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.
MSI B550-A PRO four-position headers, DC mode — source-scoped contact map
PinSignalWhat it doesStatus
1GroundGround reference and return.Device-specific
Sources
2Voltage ControlControl, detection or configuration connection; check the source and device.Device-specific
Sources
3SenseControl, detection or configuration connection; check the source and device.Device-specific
Sources
4NCNot connected or absent in this named wiring.Not connected
Sources
Sources (1)

Noctua NF-A8 PWM, 12 V

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

Product specification numbers the fan-cable contacts; white paper identifies a female cable and shows wire colors. A numeric mating-face versus rear-view drawing is not established.

  • P344 4-pin fan — **Agree** for comparable PWM and DC modes — Different MSI board manuals agree: PWM = ground/+12 V/sense/control; DC = ground/voltage control/sense/NC. A adds GIGABYTE; B adds the Noctua PWM white paper and NF-A8 PWM specification. B supplies fan-side manufacturer evidence that A lacked; the Intel fan standard itself remains unavailable.
  • White paper also covers 5 V and 24 V fans, but this numbered variant is the named 12 V NF-A8 PWM only.
  • A four-pin shell does not identify voltage. Unexamined 5 V/24 V models, proprietary headers and cable-rear numbering remain unverified.
4-pin PWM PC fan engineering referenceProduct specification numbers the fan-cable contacts; white paper identifies a female cable and shows wire colors. A numeric mating-face versus rear-view drawing is not established.SCHEMATIC · physical positions unconfirmedNot to scale · check the named wiring and device manual1: Ground (GND), black (device_specific)12: Voltage (Vcc), yellow (device_specific)23: RPM Signal, green (device_specific)34: PWM Signal, blue (device_specific)4powergrounddataConfigshieldNCUnknown
Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.
Noctua NF-A8 PWM, 12 V — source-scoped contact map
PinSignalWhat it doesStatus
1Ground (GND), blackGround reference and return.Device-specific
Sources
2Voltage (Vcc), yellowPower connection (Voltage (Vcc), yellow). Check the specified supply.Device-specific
Sources
3RPM Signal, greenWire colour for this termination: RPM Signal, green.Device-specific
Sources
4PWM Signal, blueWire colour for this termination: PWM Signal, blue.Device-specific
Sources
Sources (2)
  • S837 · Noctua · NF-A8 PWM — Specifications

    Undated live manufacturer specification page; accessed 2026-10-21 · Specifications > Extended specifications > Electrical specifications, Rated voltage and Pin configuration rows; Mechanical specifications > Connector type

  • S838 · Noctua · Noctua PWM specifications white paper

    No printed revision/date; PDF metadata creation 2023-12-21 · PDF p.2, Connectors and cables; PDF p.3, Pin configuration (12 V illustration) and Tachometer output signal; PDF p.6, PWM control input signal

Important boundary

This reference establishes only the specific manufacturer-documented family and example noted in the sources. It does not verify an arbitrary mating pair, cable orientation, electrical rating or device combination. Stop and consult original documents for the exact products.

Source-scoped V142 recognition check

MSI B550-A PRO CPU_FAN1 / PUMP_FAN1 / SYS_FAN1–6. Four aligned contacts and a guide cue in the inspected board diagram. Contact count does not select the control mode. Verify board model, header label, configured mode and the fan rating. Still unresolved: Exact connector manufacturer, housing dimensions and installed fan approval. See the internal-header field reference for source revision, observation limits and the comparison.

Your next step

Move from the form to the requirement.

Read the engineering reference Source-scoped details, orientation and explicit unknowns.Work through a connection Choose your task before deciding on a cable.Explore this evidence trail Inspect the claims and their dependencies. (private workspace)

The source trail

Evidence for this page

AI-assisted inspection is not independent engineering review. Source scope and access limitations are disclosed below. Procedural checklists are editorial requirements, not hardware measurements.

Back to first citation ↑
C344ASource checked · pending review

Noctua distinguishes its four-pin PWM fan connection by a fourth control signal; three-pin motherboard connection may not provide PWM control.

Noctua · Noctua 3-pin and 4-pin motherboard fan FAQ ↗

Locator: 3-pin fan on 4-pin PWM header; 4-pin fan on 3-pin header; PWM versus DC control
Access: public page. Fan color, connector shape and header modes vary; not a universal polarity or current-rating certificate.

S454: full source recordNoctua · Noctua microcontroller fan control guide ↗

Locator: Introduction / What are the wires of my 4-pin fan used for?
Access: public page. No color scheme, wiring voltage, or connector variant is inferred for other makers.

S455: full source recordInspect review dependencies → (private workspace)

Claim scope: Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.. Next review due 2027-01-07.

Back to first citation ↑
C344BSource checked · pending review

Motherboard documentation—not the number of header pins—determines whether its fourth position is implemented as PWM.

Noctua · Noctua 3-pin and 4-pin motherboard fan FAQ ↗

Locator: 3-pin fan on 4-pin PWM header; 4-pin fan on 3-pin header; PWM versus DC control
Access: public page. Fan color, connector shape and header modes vary; not a universal polarity or current-rating certificate.

S454: full source recordNoctua · Noctua microcontroller fan control guide ↗

Locator: Introduction / What are the wires of my 4-pin fan used for?
Access: public page. No color scheme, wiring voltage, or connector variant is inferred for other makers.

S455: full source recordInspect review dependencies → (private workspace)

Claim scope: Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.. Next review due 2027-01-07.

Back to first citation ↑
C344CSource checked · pending review

Noctua distinguishes the female fan-cable connector from male PCB headers and male cable connectors.

Noctua · Noctua PWM specifications white paper — connector roles and voltage scope ↗

Locator: PDF pp.1–3: scope, cable/PCB roles and connector images. PDF pages 2–3 visually inspected. No publication revision/date identified; not asserted current-revision equivalent.
Access: public pdf text. Observed document is not a real-hardware inspection, installed-device approval, wiring guide, current revision guarantee or manufacturing specification.

S592: full source recordInspect review dependencies → (private workspace)

Claim scope: V142: named MSI B550-A PRO manual version 6.0 (2024/02) or explicitly identified Noctua family only. Role/recognition evidence, not generic wiring, safe mating, pinout approval, dimensions or installed-device certification.. Next review due 2027-01-11.

Back to first citation ↑
C344DSource checked · pending review

Noctua’s PWM white paper covers 5V, 12V and 24V four-pin models unless otherwise stated.

Noctua · Noctua PWM specifications white paper — connector roles and voltage scope ↗

Locator: PDF pp.1–3: scope, cable/PCB roles and connector images. PDF pages 2–3 visually inspected. No publication revision/date identified; not asserted current-revision equivalent.
Access: public pdf text. Observed document is not a real-hardware inspection, installed-device approval, wiring guide, current revision guarantee or manufacturing specification.

S592: full source recordInspect review dependencies → (private workspace)

Claim scope: V142: named MSI B550-A PRO manual version 6.0 (2024/02) or explicitly identified Noctua family only. Role/recognition evidence, not generic wiring, safe mating, pinout approval, dimensions or installed-device certification.. Next review due 2027-01-11.

Back to first citation ↑
C344ESource checked · pending review

B550-A PRO lists Auto for CPU_FAN1, PWM for PUMP_FAN1 and DC for SYS_FAN1–6 as default modes.

MSI · MSI B550-A PRO User Guide, version 6.0 (2024/02) ↗

Locator: PDF pp.33, 36–38, 40–41; p.59 / printed ix revision history. Source diagrams visually inspected at zero-based pages 32,35,36,37,39,40,58.
Access: public pdf text. Observed document is not a real-hardware inspection, installed-device approval, wiring guide, current revision guarantee or manufacturing specification.

S591: full source recordInspect review dependencies → (private workspace)

Claim scope: V142: named MSI B550-A PRO manual version 6.0 (2024/02) or explicitly identified Noctua family only. Role/recognition evidence, not generic wiring, safe mating, pinout approval, dimensions or installed-device certification.. Next review due 2027-01-11.

Suggest a correction to this field note →

Put this field note to work.

Add to discovery trayRecord an unsaved candidate (private workspace)

Candidate selection does not confirm the identity or capabilities of your physical item.

Evidence behind this page

Scope first. Source second. Approval separate.

4 linked sources · 5 scoped claims · 0 sources with inspection/access flags.

Page scope: evidence_first_v103_pc_and_jst

Assessment 2026-10-22 · earliest scheduled source review 2027-01-07. This is a recorded-date assessment, not a live source check. Page-level independent review is not established by this panel.

Inspect 4 source scopes, access limits and dates

S454 · Noctua 3-pin and 4-pin motherboard fan FAQ

Noctua · Unclassified publisher domain · inspected 2026-10-09 · due 2027-01-07

Within inspection window

Scoped support: Fan-family contact-count and conditional motherboard control; Noctua examples only.

Not established / limitations: Fan color, connector shape and header modes vary; not a universal polarity or current-rating certificate.

Locator: 3-pin fan on 4-pin PWM header; 4-pin fan on 3-pin header; PWM versus DC control

S455 · Noctua microcontroller fan control guide

Noctua · Unclassified publisher domain · inspected 2026-10-09 · due 2027-01-07

Within inspection window

Scoped support: Separate power, speed-sense and PWM functions in named Noctua 4-pin fans.

Not established / limitations: No color scheme, wiring voltage, or connector variant is inferred for other makers.

Locator: Introduction / What are the wires of my 4-pin fan used for?

S591 · MSI B550-A PRO User Guide, version 6.0 (2024/02)

MSI · Unclassified publisher domain · inspected 2026-10-13 · due 2027-01-11

Within inspection window

Scoped support: Named B550-A PRO board header identities, diagram-level contact/key arrangements, control modes and RGB mismatch warnings.

Not established / limitations: Observed document is not a real-hardware inspection, installed-device approval, wiring guide, current revision guarantee or manufacturing specification.

Locator: PDF pp.33, 36–38, 40–41; p.59 / printed ix revision history. Source diagrams visually inspected at zero-based pages 32,35,36,37,39,40,58.

S592 · Noctua PWM specifications white paper — connector roles and voltage scope

Noctua · Unclassified publisher domain · inspected 2026-10-13 · due 2027-01-11

Within inspection window

Scoped support: Manufacturer-wide bounded 4-pin PWM fan family; female cable versus male board role and 5/12/24V model distinction.

Not established / limitations: Observed document is not a real-hardware inspection, installed-device approval, wiring guide, current revision guarantee or manufacturing specification.

Locator: PDF pp.1–3: scope, cable/PCB roles and connector images. PDF pages 2–3 visually inspected. No publication revision/date identified; not asserted current-revision equivalent.

Trace 5 claims to their source records

C344A · P344

Noctua distinguishes its four-pin PWM fan connection by a fourth control signal; three-pin motherboard connection may not provide PWM control.

Claim scope: Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.

Source links: S454 · S455 · Evidence trail → (private workspace)

C344B · P344

Motherboard documentation—not the number of header pins—determines whether its fourth position is implemented as PWM.

Claim scope: Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.

Source links: S454 · S455 · Evidence trail → (private workspace)

C344C · P344

Noctua distinguishes the female fan-cable connector from male PCB headers and male cable connectors.

Claim scope: V142: named MSI B550-A PRO manual version 6.0 (2024/02) or explicitly identified Noctua family only. Role/recognition evidence, not generic wiring, safe mating, pinout approval, dimensions or installed-device certification.

Source links: S592 · Evidence trail → (private workspace)

C344D · P344

Noctua’s PWM white paper covers 5V, 12V and 24V four-pin models unless otherwise stated.

Claim scope: V142: named MSI B550-A PRO manual version 6.0 (2024/02) or explicitly identified Noctua family only. Role/recognition evidence, not generic wiring, safe mating, pinout approval, dimensions or installed-device certification.

Source links: S592 · Evidence trail → (private workspace)

C344E · P344

B550-A PRO lists Auto for CPU_FAN1, PWM for PUMP_FAN1 and DC for SYS_FAN1–6 as default modes.

Claim scope: V142: named MSI B550-A PRO manual version 6.0 (2024/02) or explicitly identified Noctua family only. Role/recognition evidence, not generic wiring, safe mating, pinout approval, dimensions or installed-device certification.

Source links: S591 · Evidence trail → (private workspace)

Prepare this page for review → (private workspace)Read the evidence method →

Recorded evidence only. An inspection date, publisher label, source link or generated packet is not independent technical review, hardware testing, fabrication approval or a compatibility verdict.