At GTC DC last month, Jensen Huang showed off components of the Vera Rubin NVL144 platform. First, here's the latest roadmap, which now includes BlueField-4 and BlueField-5. For more on that, see BWR Episode 4 .  Source: Nvidia Below is the Vera Rubin compute tray, which includes four Rubin GPUs. By GPU, we mean package not die. Note that the Blackwell NVL72 and Rubin NVL144 both have 72 GPU packages, but the NVL144 moniker denotes Nvidia's new math counting die. The company didn't rename the Blackwell configuration, even though that GPU also has two die. Each compute tray has two Vera CPUs, which are 88-core Arm processors. Two GPUs connect with one CPU using NVLink-C2C, a coherent variant of NVLink. Although the roadmap above shows CX9 as 1600G, each ConnectX-9 is actually 800Gbps, requiring eight chips to deliver the aggregate 800GB/s quoted for the tray. That means each GPU has a pair of 800G Ethernet/InfiniBand NICs for scale-out networking. Finally, a single BlueField...

 The Byrne-Wheeler Report Episode 4 discusses the RISC-V Summit NA, BlueField-4, SambaNova, and AWS Rainier. You can skip to 12:12 if you're uninterested in RISC-V.

October was a busy month, between the OCP Global Summit and being the lead author on the LightCounting switch report. The new report adds another level of granularity to the scale-up switch forecast, which incorporates NVLink, UALink, Scale-Up Ethernet (SUE), and non-Nvidia proprietary interconnects. There are many other changes to the report, including revisions to the methodology for the co-packaged optics (CPO) forecast. The newsletter summary is freely available: Co-packaged Optics Grow the Scale-out Switch Pie Source: Wheeler's Network

In Episode 3, Joe and Bob discuss OCP-related announcements and the AMD-OpenAI deal. 00:00:26 OCP recap 00:01 AMD Helios rack 00:06:46 Broadcom Thor Ultra 00:12:32 Intel Crescent Island 00:19:11 AMD-OpenAI deal 00:26:33 Signing off

 In case you missed it, Episode 2 of The Byrne-Wheeler Report is available. In this episode, Joe and I discuss the Intel-Nvidia deal, the Nvidia-Enfabrica combination, and Upscale AI's launch.

My colleague Joe Byrne and I launched a video podcast covering the latest news in the chip world. Episode 1 covers Hot Interconnects and Hot Chips news from August as well as Arm's Lumex announcement and Nvidia's Rubin CPX. We hope you enjoy this new format, which will complement our respective blogs.  

Source: Hot Chips The accelerated life cycles that AI is driving woke up a normally sleepy August. Held virtually, Hot Interconnects (HotI 2025) spanned three days with a mix of invited talks, sponsor talks, and tutorials. Some of the brief sponsor talks merely previewed larger disclosures at Hot Chips, which was held at Stanford University the following week. This year, Hot Chips’ agenda included an Optical session that featured three startups plus Nvidia. It also included Networking and Machine Learning (ML) sessions with talks from leading vendors. Although Nvidia was the marquee name in Hot Chips' Optical session, Gilad Shainer's talk on co-packaged silicon photonics lacked any new technical details on the company's CPO switches. Instead, the company used the event to announce Spectrum-XGS, which extends its Spectrum-X Ethernet solution across data centers. Nvidia calls this "scale-across" networking because it primarily targets data center clusters, but it is...