The majority of pins on the AM4 array are dedicated to power and ground to ensure stability. The VSS pins (Ground) are the most abundant on the die. In the AM4 pinout tables, VSS pins are often highlighted in grey or black, while VDD (Core Voltage) pins deliver the raw power needed for Zen architectures.
: Voltage for the System-on-Chip (SoC) components, including the memory controller and integrated graphics.
: Includes signals for USB (e.g., USB_SS_RX/TX), DisplayPort (DP0_TX), and system control like THERMTRIP_L for thermal protection. Community Resources & Diagrams am4 pinout diagram exclusive
Before the comprehensive GitHub resources emerged, the Reddit community, led by users like u/cole_8888 , worked to create a pinout diagram from leaks and community-driven discovery. This grassroots effort resulted in several valuable resources:
With the transition to AM5 (LGA 1718), you might ask: Why care about AM4? The majority of pins on the AM4 array
: The socket provides 24 lanes, though the silicon often contains more that are repurposed for other functions. Pins such as P_GFX_TXP and P_GFX_TXN are dedicated to high-speed graphics data. Power Delivery (Voltage Rails) : VDDCR_CPU : Main core voltage supply for the processor.
Synchronise differential data transfers between the CPU and RAM modules. PCI Express (PCIe) and Storage Linkages : Voltage for the System-on-Chip (SoC) components, including
Separate pairs for data (DQ), data strobes (DQS), and address/control (ADDR/CTRL). VDDIO: 1.2V to 1.35V power for DDR4 modules. C. PCIe Lanes (Graphics and Storage)
Dominated by high-speed differential pairs for PCIe, USB, and memory controllers. 2. Key Signal Mapping and Pin Functions
Disclaimer: This information is compiled for educational purposes. Misreading pinouts can destroy hardware. Proceed with caution.
Provides the dedicated voltage required for the DDR4 memory interface.