NVIDIA Announces the Blackwell GPU Architecture

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NVIDIA announced the Blackwell GPU architecture at GTC on March 18, 2024 in a keynote where Jensen Huang said the company was “not in the semiconductor business — we’re in the infrastructure business.” The flagship B200 GPU used two connected dies (the GB202 silicon) totaling 208 billion transistors on TSMC’s 4NP custom process — more than double the H100’s 80 billion transistors on 4N. The B200 delivered 20 petaFLOPS at FP4, compared to the H100’s 4 petaFLOPS at FP8 (halving precision doubles throughput, so the increase was partly from precision and partly from transistor count). HBM3e memory reached 192 GB per B200 with 8 TB/s bandwidth — nearly 2.4× the H100’s 3.35 TB/s.

Blackwell’s second-generation Transformer Engine added FP4 (4-bit floating point) support for inference, extending the first-generation H100 Transformer Engine’s FP8. The engine dynamically selected precision per layer — using FP8 for layers where accuracy loss was minimal and FP16 or BF16 for sensitive attention layers — allowing inference at 2–4× the throughput of FP8 without retraining models from scratch. Fifth-generation NVLink (NVLink 5) provided 1.8 TB/s bidirectional bandwidth between GPUs in a DGX B200 system (8 GPUs) and scaled to 576 GPUs in a single NVLink fabric domain via NVLink switches.

The GB200 NVL72 — 36 Grace CPUs and 72 B200 GPUs in a single rack connected through NVLink 5 — was the primary reference architecture: 72 GPUs sharing a coherent memory pool of 13.8 TB of HBM3e, enabling a single model too large for any individual GPU to run across the full rack as one logical compute unit. Blackwell NVL72 racks consumed up to 120 kW — requiring purpose-built liquid cooling at the rack level — and were projected to start shipping to cloud providers in Q3 2024. Microsoft, Google, Oracle, and Amazon all pre-announced purchases at the GTC announcement.

Why This Moment Mattered

The event is useful to read as a platform signal, not only as a product announcement. In the short term, it gave users and developers something concrete to react to. In the longer term, it became part of a larger pattern in hardware, computing, history: hardware, software, services, and user expectations were all changing at the same time.

A good technology milestone usually matters for more than one audience. Enthusiasts notice the specifications or the interface first. Developers ask what new assumptions they can make. Companies look at cost, compatibility, and strategy. Ordinary users mostly notice whether the result makes their devices faster, easier, safer, or more useful.

The Broader Context

This period of computing was shaped by several overlapping transitions: faster networks, more capable mobile devices, cloud infrastructure, stronger security expectations, and software that changed continuously after release. Against that background, the milestone was not an isolated headline. It was one piece of a much larger movement away from static products and toward connected platforms.

That context helps explain why some announcements that looked modest at the time became important later. A browser feature, processor change, development tool, or platform policy can alter what future products are able to assume. Once enough users, developers, and vendors adapt, the new assumption becomes normal.

Looking Back

The value of revisiting the moment is that it shows how technology history is built from many medium-sized steps. Some are celebrated immediately, while others become meaningful only after the ecosystem catches up.

Looking back also keeps the story balanced. Progress usually brings tradeoffs: performance against power use, openness against consistency, convenience against control, and speed against stability. The most interesting milestones are the ones that reveal those tradeoffs clearly. This one belongs in that category because it helps explain not just what changed, but why the direction of computing kept moving the way it did.