Intriguing AMD FCH-on-a-Stick Add-on Card Makes an AMD Chipset Look Like It’s Running an Intel CPU

AMD’s X670E and X870E Chipsets: Expanding PCIe and SATA Capabilities

AMD’s high-end X670E and X870E chipsets are engineered by combining two “Promontory 21” FCH (Fusion Controller Hub) chips. Each FCH chip connects via a PCI Express 4.0 x4 interface and delivers eight PCIe 4.0 lanes along with four SATA 6 Gbps ports. Notably, these SATA ports can be reconfigured as four additional PCIe Gen 3 lanes, offering flexibility for various storage and expansion needs.

When paired together, the X670E or X870E chipset provides a total of 12 PCIe 4.0 lanes and up to eight SATA 6 Gbps ports, significantly enhancing the platform’s connectivity options. This architecture is particularly beneficial for users seeking to maximize storage and peripheral expansion on their AMD systems.

Innovative Add-On Card Brings Chipset Expansion to More Platforms

In a creative move, a hardware manufacturer has developed an add-on card featuring one of these Promontory 21 FCH chips. This card is designed to upgrade single-FCH platforms such as AMD’s B650, B850, or X870 motherboards, enabling users to add more PCIe lanes and additional M.2 slots, as well as extra SATA ports. This solution is ideal for enthusiasts who require expanded storage capabilities without replacing their entire motherboard.

The add-on card is equipped with four M.2 slots—two on each side—and four SATA 6 Gbps ports. At least two of the M.2 slots support PCIe Gen 4 x4 speeds, while the remaining slots may operate at Gen 3 x4 or M.2-SATA speeds, depending on the configuration and whether the SATA ports are in use.

Unexpected Results on Intel Motherboards

In an interesting twist, PC enthusiasts in China experimented by installing this AMD chipset add-on card on an Intel motherboard. This led to some amusing outcomes: system utilities like AIDA64 misidentified the Promontory 21 chip as the main platform chipset, creating the illusion of an Intel processor running on an AMD chipset motherboard. This highlights the versatility—and occasional quirks—of modern PC hardware compatibility.

While this add-on card offers a unique way to expand PCIe and SATA connectivity, details about its availability remain unclear. For now, it stands as an intriguing example of how chipset technology can be repurposed to meet the evolving needs of PC builders and enthusiasts.