
AMD has recently unveiled its innovative Pensando Pollara 400 AI NIC at Hot Chips 2025, marking the introduction of the first Ultra Ethernet Consortium (UEC)-ready AI Network Interface Card (NIC) in the industry.
AMD Enhances Performance by 25% with the 400GbE Pensando Pollara 400 AI NIC
Building upon its previous development, AMD showcased the Pensando Pollara 400 last year. This state-of-the-art NIC, designed specifically for AI systems, boasts a remarkable bandwidth of 400 Gbps, putting it in direct competition with NVIDIA’s ConnectX-7. However, NVIDIA has also launched the more advanced ConnectX-8, offering impressive 800GbE speeds with their latest Blackwell Ultra systems.

The Pensando Pollara 400 comes packed with several cutting-edge features:
- Programmable Hardware Pipeline
- Up To 1.25x Performance Enhancement
- 400 Gbps Throughput
- Open Ecosystem Compatibility
- UEC Ready RDMA Capabilities
- Reduced Job Completion Time
- Exceptional Availability

The architecture of the Pensando Networking solutions is closely aligned with AMD’s existing Data Center architectures, particularly the EPYC and Instinct families, which utilize PCIe switches to efficiently connect NICs and CPUs.

Importantly, the Pensando NIC operates without a PCIe switch and interfaces directly with a Gen5 x16 connection. The underlying architecture is outlined in the following diagram:

Through the utilization of a P4 architecture, the Pensando Pollara 400 AI NIC achieves remarkable efficiency.

The architecture’s significant components encompass the Table Engine (TE), responsible for generating table keys from the package header vector, along with executing specific memory reads based on data type.

The design also features a Match Processing Unit (MPU), a specialized processor utilizing optimized opcodes for field manipulation, facilitating distinct memory, table, and PHV interfaces.

Additionally, innovations such as Virtual Address to Physical Address (va2pa) translation capabilities enhance system performance further.

In terms of atomic memory operations, AMD has implemented them adjacent to SRAM systems for greater efficiency.

The Pipeline Cache Coherency employs invalidate/update logic, ensuring P4 coherency operates effectively on an address range basis.

AMD identifies several challenges impacting AI system performance across Scale-out networks. Issues such as inefficient link utilization tied to ECMP load balancing, network congestion, and packet loss hinder overall effectiveness.

The company also highlights that AI networks experience significantly higher utilization rates compared to general-purpose networks, often pushing the limits of network bandwidth availability.

AMD presents the Ultra Ethernet Consortium (UEC) as a vital solution to overcoming these obstacles. The UEC fosters an open, interoperable, high-performance framework designed to address the networking requirements essential for AI and high-performance computing (HPC) applications at scale.

Designed for efficiency and affordability, the UEC aims to fulfill the significant demands increasingly placed on modern data networks.

Additional advantages of the UEC include enhanced routing techniques and network management solutions designed to address issues related to congestion and packet loss.

In summary, AMD’s Pensando Pollara 400 AI UEC-ready RDMA NIC demonstrates a 25% performance improvement compared to RoCEv2 with 4 Qpairs, and a notable 40% increase over RoCEv2 with 1 Qpair, solidifying its role as a leader in networking technology.
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