Power Supply Connectors

Motherboard (Mainboard) Connector

• Standard is now a $24$-pin plug.
• Legacy $20+4$ design can join to form the same $24$-pin size.

CPU (Processor) Power Connector

• Supplies power near CPU socket, labeled "CPU_PWR".
• Common sizes: $8$-pin (current), $4$-pin (older), or $4+4$ that combine into $8$.

PCI Express (PCIe) Power

• Slot delivers up to $25$ W (older boards) or $75$ W (newer boards).
• High-draw cards add $6$- or $8$-pin plugs on the card itself.
• PSU cables: fixed $8$-pin or $6+2$ (forms $8$ when joined).

SATA Power

• $15$-pin L-shaped connector for SATA HDD, SSD, and optical drives.

Molex (Legacy)

• $4$-pin connector for IDE drives and very old optical media devices.

Y Adapters / Splitters

• Split one connector into $2$ identical ones.
• Can also convert between types (e.g., PCIe → SATA or Molex).

General Rules

• Choose connector type to match the device.
• All plugs are keyed; they fit only one way, preventing polarity errors.