A Motherboard (sometimes alternatively known as the mainboard, system board, planar board or logic board, or colloquially, a mobo) is the main printed circuit board (PCB) found in computers and other expandable systems. It holds and allows communication between many of the crucial electronic components. Here are complementary connectors of motherboards.
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Page 9 0Y0561.book Page 7 Thursday, May 8, 2003 9:45 AM Install the replacement system board and I/O shield assembly: Line up the parallel port connector with the opening on the back of the computer. Insert the back-panel connectors into the openings at the back of the computer and lower the system board into place. Intel Core i7-8700 (3.2 GHz base frequency, up to 4.6 GHz with Intel Turbo Boost Technology, 12 MB cache, 6 cores) 65 W. Intel Core i3-8100 (3.6 GHz base frequency, 6 MB cache, 4 cores) 65 W. Intel Pentium Gold G5400 (3.7 GHz base frequency, 4 MB cache, 2 cores) 54 W - 58 W.

Intel High Definition Audio connectorIntel HD Audio analog front panel dongles can support up to two analog audio jacks, each of which signals user connection, or disconnection.
Motherboard 2-pin fan connector
Motherboard 3 pin CPU or Case Cooling fan connector
Motherboard 4 pin CPU PWM fan connectorFor 4-Wire Pulse Width Modulation (PWM) Controlled Fans
PC Speaker connector
RS232 serial motherboard header connectorRS232 serial is also called COM port
USB 2.0/1.1 Header
USB 3.0 HeaderUSB 3.0 is the successor of USB 2.0. USB 3 reduces the time required for data transmission, reduces power consumption, and is backward compatible with USB 2.0
USB 3.0 Header to USB 2.0 HeaderUSB 3.0 contains normal USB 2.0 connections. This is commonly for PC cases that have ports that don't match the Available headers. Converting from 3.0 -> 2.0 is flawless, but converting from 2.0 -> 3.0 will make your 3.0 ports active, but will only function at 2.0 speeds.
USB header internal connectorUsed for card-edge bracket additinal USB ports and internal cardreaders. This is very old and does not match most modern mother board usb headers.

Apple Pinouts

Apple BCM94360 connectorApple PCIe connector for BCM94360 Series WiFi Adapters
Apple Fan Connector (6 pin)Late model Apple laptops, iMacs and Mac Pros have analog speed control fans. This pinout and color scheme applies to fans made by Delta Electronics, models BFB0412HB (Apple P/N 603-5520), BFB0612H (Apple P/N 603-5519), BFB0812H (Apple P/N 603-6624), and others.
Apple Mac Pro dual fan connectorSome Apple Mac Pros use a single 8 pin connector for two fans. Apple uses various color schemes for wires. This dual fan connector usually has all black wires.
Apple Motherboard 4 pin CPU PWM fan connector

Dell Pinouts

Dell 5 pin Fan connector to standard 4 pin PWM FanThis is to fit a standard 4pin fan to a dell motherboard 5pin CPU (speed controlled) fan connector (essentially, you just swap pins 1 & 3 on the standard connector)
Dell Dimension 2350, 2400 internal USB & Speaker20 Pin Front panel USB, Speaker (Optional MIC) Proprietary
Dell Dimension 3100/E310 and 5150 I/O Front Panel AssemblyWARNING. Similar to Optiplex GX BUT +5v & Gnd differs !
DELL Dimension 9200 FanFan for CPU or HD
Dell GX270 SER2 motherboard connector
Dell JN454 Front Panel I/O
Dell Optiplex 360, 7010 motherboard power switch connectorDell Optiplex 360, 990, 7010, 9010 motherboard power switch connector
Dell OptiPlex 745 & Dimension C521 I/O Panel Assembly pin-outSimilar to Dell Dimension 3100 (no Mic) and 5150 (USB skts are counted from the left)
Dell Optiplex 745 SFF internal USB connectorFor Dell Optiplex 745 SFF-Not tested on other Dell's models.
Dell OptiPlex GX280 Front Panel I/O Assembly Pin-Outs Similar to other Dell I/O assembly boards, it is a board with USB connectors and a headphone connector. It also has a connection to the Control Panel Board (Power switch and LEDs).
Dell Optiplex Internal Serial PortDell Optiplex Internal Serial Port-3.3V Signaling
Dell PowerEdge 2300 internal USB connector10 pin one row special USB connector
Dell Vostro 470 front panel connector for LEDs and switch (F_PANEL)12-way header with removable pins.

ECS Pinouts

ECS LPC_DEBUG connectorCan be found on some new ECS motherboards

HP Pinouts

HP Compaq ProLiant ML310 G1 4-pin CPU FanProprietary 4 pin CPU Fan connector
HP Compaq ProLiant ML310 G1 Case FanProprietary 5 pin Fan connector
HP Compaq ProLiant ML310 G1 Second AUX Power ConnectorMolex 10 Pin PSU AUX Connector
HP dc7900 secondary COM port header cableSecondary COM port cable for the Hewlett Packard dc7900 series workstations.
HP Microserver 12 FANHP Microserver 12 FAN Pinout
HP ML310 Front Panel Header
HP ML350 G6 Motherboard Fan ConnectorHP ML350 G6 Motherboard Fan Connector Pinout
HP Server 5 pin Fan connectorHP Server 5 pin Fan connector (DL580 G7)
HP Vectra VE 5/75 System Panel Header (PNL-A)6-pin Panel This header accomodates several system panel functions

HPE Pinouts

HPE Hard Drive Backplane Power Cable 661361-001Cable used to connect an extra bay on HPE Generation 8 servers (ML350p G8 for example). Cable part of cable kit 667266-001 containing Hard Drive Power Cable, short SAS cable and dual connectors graphics power cable.

Dell E145483 Motherboard Manual User

Intel High Definition Audio connectorIntel HD Audio analog front panel dongles can support up to two analog audio jacks, each of which signals user connection, or disconnection.
Motherboard 2-pin fan connector
Motherboard 3 pin CPU or Case Cooling fan connector
Motherboard 4 pin CPU PWM fan connectorFor 4-Wire Pulse Width Modulation (PWM) Controlled Fans
PC Speaker connector
RS232 serial motherboard header connectorRS232 serial is also called COM port
USB 2.0/1.1 Header
USB 3.0 HeaderUSB 3.0 is the successor of USB 2.0. USB 3 reduces the time required for data transmission, reduces power consumption, and is backward compatible with USB 2.0
USB 3.0 Header to USB 2.0 HeaderUSB 3.0 contains normal USB 2.0 connections. This is commonly for PC cases that have ports that don't match the Available headers. Converting from 3.0 -> 2.0 is flawless, but converting from 2.0 -> 3.0 will make your 3.0 ports active, but will only function at 2.0 speeds.
USB header internal connectorUsed for card-edge bracket additinal USB ports and internal cardreaders. This is very old and does not match most modern mother board usb headers.

Apple Pinouts

Apple BCM94360 connectorApple PCIe connector for BCM94360 Series WiFi Adapters
Apple Fan Connector (6 pin)Late model Apple laptops, iMacs and Mac Pros have analog speed control fans. This pinout and color scheme applies to fans made by Delta Electronics, models BFB0412HB (Apple P/N 603-5520), BFB0612H (Apple P/N 603-5519), BFB0812H (Apple P/N 603-6624), and others.
Apple Mac Pro dual fan connectorSome Apple Mac Pros use a single 8 pin connector for two fans. Apple uses various color schemes for wires. This dual fan connector usually has all black wires.
Apple Motherboard 4 pin CPU PWM fan connector

Dell E145483 Motherboard Manual Software

Dell Pinouts

Dell 5 pin Fan connector to standard 4 pin PWM FanThis is to fit a standard 4pin fan to a dell motherboard 5pin CPU (speed controlled) fan connector (essentially, you just swap pins 1 &am