MSI documents its three-pin five-volt JRAINBOW connector for addressable RGB lighting; it must not be treated as an ordinary four-pin twelve-volt JRGB connection.
Also calledJRAINBOW 5VARGB header 3 pin5V digital RGB headeraddressable RGB motherboard
Voltage and signaling class are more important than a superficial resemblance between small lighting headers.
Look for
Find the JRAINBOW/ARGB label and 5 V marking for the exact motherboard; confirm the accessory’s intended connection before handling it.
Three-quarter view Computer-generated illustration with prior AI visual review. Not a photograph, measurement or compatibility check. Independent technical and rights review pending.
Mating face Computer-generated illustration with prior AI visual review. Not a photograph, measurement or compatibility check. Independent technical and rights review pending.
Fitted in place Computer-generated illustration with prior AI visual review. Not a photograph, measurement or compatibility check. Independent technical and rights review pending.
Recognition drawing Original schematic, not to scale. Drawing review pending.
Image inspection / P348
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.
(private workspace)
P348 / Source-observed physical study
5V ARGB / JRAINBOW
MSI B550-A PRO JRAINBOW1–2
Board-side plan layout, following the cited diagram orientation · Board header
Not to scale. Technical and rights review pending.
Inspect view & provenance ↗ (private workspace)
INTERNAL SYSTEMS / HEADERS
5 V addressable RGB is not the 12 V RGB standard
No. In MSI’s cited documentation, JRAINBOW is a specified 5 V addressable lighting output, distinct from 12 V JRGB. Do not infer that all three-pin motherboard headers—including fan, ARGB and other proprietary lighting variants—share voltage, pin assignment or signal type.
Lighting: check the voltage first. Original qualitative role diagram; not mechanical artwork, not to scale or a wiring map. Source context S458.
Three checks before proceeding
Read both hardware manuals and verify the exact 5 V addressable wiring scheme.
Match the connector arrow, spacing and manufacturer-provided control cable.
Do not attach to a 12 V header or unidentified fan/accessory socket.
One mistake to avoid
Matching only the number of contacts and not the marked power/signal function.
Claim-specific evidence remains in the canonical record. Concept diagrams do not show any safe wiring or mechanical mating geometry.
The useful distinction
Recognize it. Then verify it.
MSI documents its three-pin five-volt JRAINBOW connector for addressable RGB lighting; it must not be treated as an ordinary four-pin twelve-volt JRGB connection. [C348A]
MSI directs users to turn off power, check model-specific manuals, and warns that mixing five-volt strips with twelve-volt JRGB damages equipment. [C348B]
B550-A PRO describes JRAINBOW1–2 as 5V WS2812B addressable-LED connections. [C348C]
The JRAINBOW source diagram leaves position 3 absent within a four-position span. [C348D]
MSI requires power-supply shutdown and disconnection from the outlet before LED-strip changes. [C348E]
Identify the documented form
Identify MSI JRAINBOW by its manual, absent position and addressable-lighting role.
The JRAINBOW family is distinct from ordinary JRGB; the source drawing’s absent position is meaningful rather than a missing accidental contact. S458 · S591
MSI names the supported addressable-lighting role for the cited board; that does not turn every similar small plug into that interface. S591
Documented identity facts; exact part and variant scope remains with each value
Nominal contacts
3 (MSI JRAINBOW)S458Recorded source-scoped values; named examples do not describe every family variant or establish compatibility. Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.
Positions / cavity span
4 (Claim C348D); 4 (MSI B550-A PRO four-position span, position 3 absent); 4 (MSI B550-A PRO JRAINBOW1–2)S591 · S757Separate exact examples; retain each value’s source, role, axis and part 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. Exact named example MSI B550-A PRO JRAINBOW1–2: Device-specific5V addressable RGB header. Exact example only; no universal geometry, electrical compatibility, fabrication approval or wiring instruction. No universalARGBpitch, wire-sideview or specimenmarkings inferred.
Populated contacts
3 (MSI JRAINBOW, positions 1/2/4); 3 (MSI B550-A PRO JRAINBOW1–2)S458 · S757Separate exact examples; retain each value’s source, role, axis and part scope. Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval. Exact named example MSI B550-A PRO JRAINBOW1–2: Device-specific5V addressable RGB header. Exact example only; no universal geometry, electrical compatibility, fabrication approval or wiring instruction. No universalARGBpitch, wire-sideview or specimenmarkings inferred.
Connector role
header (MSI JRAINBOW)S458Recorded source-scoped values; named examples do not describe every family variant or establish compatibility. Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.
Rows, pitch, dimensions, keying and view limits
Additional scoped facts; not a fabrication drawing or a mating approval
Contact rows
1 (MSI B550-A PRO JRAINBOW1–2)S757Separate exact examples; retain each value’s source, role, axis and part scope. Exact named example MSI B550-A PRO JRAINBOW1–2: Device-specific5V addressable RGB header. Exact example only; no universal geometry, electrical compatibility, fabrication approval or wiring instruction. No universalARGBpitch, wire-sideview or specimenmarkings inferred.
Contact pitch
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Dimensions / axis
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Coupling / latch
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Keying / polarization
absent position 3 (MSI B550-A PRO JRAINBOW)S591Recorded source-scoped values; named examples do not describe every family variant or establish compatibility. 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.
View convention
MSI p.41 numbered header sketch, pin1left; row positions1,2and4occupied, position3absent; do not renumber the gap. (MSI B550-A PRO JRAINBOW1–2)S757Separate exact examples; retain each value’s source, role, axis and part scope. Exact named example MSI B550-A PRO JRAINBOW1–2: Device-specific5V addressable RGB header. Exact example only; no universal geometry, electrical compatibility, fabrication approval or wiring instruction. No universalARGBpitch, wire-sideview or specimenmarkings inferred.
Contact gender / arrangement
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Mounting
board (Claim C348A)S458Recorded source-scoped values; named examples do not describe every family variant or establish compatibility. Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.
Shell / form
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Manufacturer
MSI (B550-A PRO JRAINBOW1-2)S591Recorded source-scoped values; named examples do not describe every family variant or establish compatibility. 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.
Series
JRAINBOW (B550-A PRO JRAINBOW1-2)S591Recorded source-scoped values; named examples do not describe every family variant or establish compatibility. 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.
Exact part / implementation
B550-A PRO JRAINBOW1-2 (B550-A PRO JRAINBOW1-2)S591Recorded source-scoped values; named examples do not describe every family variant or establish compatibility. 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.
Recorded markings
Not recordedNot recorded in a normalized source-scoped field. Consult the exact part/revision; no value inferred from illustrations.
Keep this limit: MSI requires power shutdown and disconnection before LED-strip changes. S591
Make the next check
Check the exact board and accessory designation, voltage and alignment instructions before handling the lighting lead.
Existing source inspection and AI review remain distinct from independent technical review. A matching form does not establish a safe connection.
Recorded variant and source limits
Check the exact device manual before wiring or applying power.
MSI MAG B550 TOMAHAWK JRAINBOW1~2: Per manual.
GIGABYTE B550 AORUS ELITE (AX) D_LED1/D_LED2 (comparable 5 V ARGB header, not MSI): Per manual.
MSI B550-A PRO JRAINBOW1–2: MSI p.41 JRAINBOW1–2 board sketch: four numbered positions, pin 1 left, position 3 absent, pin 4 right. Three contacts occupy 1, 2 and 4; the gap is not renumbered.
5 V addressable RGB header (MSI JRAINBOW) facts and limitations
Documented MSI JRAINBOW form
Three contacts; 5 V addressable lighting category — model check required [C348A]
Role and recognition scope
Board header — MSI B550-A PRO JRAINBOW1–2. Original qualitative study only; no wiring or fit approval. [C348C][C348D][C348E]
Mechanical dimensions
Only manufacturer-described nominal family/footprint pitch is quoted in sourced text; no measured fabrication/tolerance drawing independently approved.
Not included. Check exact device and accessory documentation.
A boundary, not an omission to guess around.
Remove PC power completely before inspecting or mating lighting headers. Check that the accessory requires five-volt addressable RGB and matches the exact motherboard’s key and polarity. Do not attach a 5 V ARGB product to a 12 V JRGB header; if the key or voltage label is unclear, stop.
Before you connect
What to check
Remove PC power completely before inspecting or mating lighting headers.
Check that the accessory requires five-volt addressable RGB and matches the exact motherboard’s key and polarity.
Do not attach a 5 V ARGB product to a 12 V JRGB header; if the key or voltage label is unclear, stop.
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.
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 JRAINBOW1–2. Three contacts across four positions, with an internal gap in the inspected view. Addressable lighting is a different documented interface. Verify the exact 5V addressable header and LED/controller documentation. Still unresolved: Other vendors’ three-pin arrangements, signal implementations and assembled-device approval. See the internal-header field reference for source revision, observation limits and the comparison.
AI-assisted inspection is not independent engineering review. Source scope and access limitations are disclosed below. Procedural checklists are editorial requirements, not hardware measurements.
Locator: JRGB connector; JRAINBOW connector; warning on voltage mismatch; motherboard manual check Access: public page. Other LED headers and proprietary variants exist. No universal header assignment or exact LED current assumption.
Claim scope: Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.. Next review due 2027-01-07.
Locator: JRGB connector; JRAINBOW connector; warning on voltage mismatch; motherboard manual check Access: public page. Other LED headers and proprietary variants exist. No universal header assignment or exact LED current assumption.
Claim scope: Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.. Next review due 2027-01-07.
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.
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.
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.
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.
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.
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.
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.
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.
Trace 5 claims to their source records
C348A · P348
MSI identifies JRAINBOW as a five-volt, three-pin addressable-RGB motherboard header.
Claim scope: Manufacturer-specific family/physical identification only. No inferred device wiring, mating verification or installation approval.
B550-A PRO describes JRAINBOW1–2 as 5V WS2812B addressable-LED connections.
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.
The JRAINBOW source diagram leaves position 3 absent within a four-position span.
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.
MSI requires power-supply shutdown and disconnection from the outlet before LED-strip changes.
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.
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.