Internal connectors there are a number of connectors

Internal
Connectors
There are a number of connectors on motherboards for components such as
power supplies, fans, and LED lights. Computer cases often have front panel
ports (e.g., USB, FireWire, or audio ports) that need to be connected to the
motherboard. These ports are connected to the motherboard's front panel
connectors, which are also called headers.
External ports that are not available on the motherboard are often added using
expansion cards.
Firmware The firmware on a motherboard is stored on integrated flash memory.
Motherboards use one of two firmware implementations:

 BIOS (Basic Input/Output System)
 UEFI (Unified Extensible Firmware Interface)
Older motherboards stored the BIOS on removable, read-only memory (ROM)
chips.
CMOS
Battery
The CMOS battery is used to keep an accurate date and time, even when the
motherboard has no power. In older motherboards, the CMOS battery was also
used to retain BIOS configuration settings, which were stored in volatile
memory called the CMOS chip.
Chipset
The chipset is a group of chips that facilitates communication between the
processor, memory, and peripheral devices.
With chipsets:
 The memory controller and graphics controller are on the CPU.
 The remaining functionality is combined into a single controller chip.
o Intel processors use the Platform Controller Hub (PCH).
o AMD processors use the Fusion Controller Hub (FCH).
 The front-side bus is replaced by the Direct Media Interface (DMI).
Support
manual
A motherboard's support manual is an excellent source of information. Support
manuals contain technical specifications as well as diagrams that identify the
motherboard's components. If you are missing a motherboard's support manual,
check the manufacturer's website.
Selecting a motherboard with the same form factor as the case and power supply is an easy way
to assure compatibility.
A typical motherboard includes the common connectors shown in the following diagram:

Repairing a motherboard is beyond the skill of most technicians and it is almost always cheaper
and faster to purchase a new one. You might also need to replace your motherboard to add new
features or to upgrade the processor. Use the following process when installing or replacing a
motherboard:
1. If you are replacing an existing motherboard, document the current CMOS settings. You
might need these settings to configure the new motherboard.
2. Install the CPU, heat sink, and memory before installing the motherboard in the case.
3. Insert the I/O shield into the case.
4. Fasten standoffs to the case, being sure to match the hole pattern on the motherboard. The
standoffs prevent the motherboard circuits from touching the system case.
5. Install the motherboard, securing it to the standoffs with insulated washers and screws.
6. Connect the power and accessory cables:
o Connect the ATX power cable and the CPU power cable.
o Connect the CPU fan power cable.
o Connect case wires (e.g., power switch, reset switch, and drive activity and power
lights).
o Connect any case fan cables.
7. Connect drives to SATA connectors.

8.