The Principle Lab

Author: The Principle Lab What Is Groq's LPU (Language Processing Unit) - and How Is It Different from a GPU? If you keep hearing "LPU" next to GPUs, you are not alone. Groq uses the term to describe a chip architecture aimed at AI inference workloads. The confusing part is simple: both an LPU and a GPU can run AI workloads. But the mental model you use to understand how work moves through the chip is different. GPU framing (CUDA) Kernels -> threads -> blocks -> grids LPU framing (Groq) Programmable assembly-line dataflow What you should watch Different programming assumptions What this is and why people care in 2025 In plain English, this is a naming and framing question. Groq calls its processor an LPU to make a point: it is designed around inference workloads and a specific ...

Author: The Principle Lab The High Bandwidth Memory Overview - From 3D-Stacked DRAM to AI Accelerators If you have ever looked at an AI accelerator spec sheet and thought, "Why is the memory a whole headline?", you are already in the right mindset. HBM matters because modern compute is often limited by data movement, not raw math. When a chip can calculate faster than it can be fed, memory bandwidth density becomes the real bottleneck. This hub is a series map: concept first, then bandwidth, then packaging, then comparisons, then the trade-offs people forget, and finally where the next standard direction is headed. Quick summary if you are in a hurry HBM is about moving a lot of data near the compute die with high energy efficiency. It is commonly paired with AI and supercomputing-class designs because the packaging is complex but the payoff is real. The key mental...

Author: The Principle Lab Why Most Consumer GPUs Don't Use HBM (and Whether HBM Is Good for Gaming) If you have ever looked at a spec sheet and thought "HBM means faster, so why not put it on every gaming GPU?", you are not alone. But memory type is not just a speed badge. It is a whole design choice that shapes packaging, compatibility, and what performance looks like in real workloads. Quick summary if you're in a hurry HBM in practice Often paired with advanced packaging and tight integration GDDR6 in practice Designed for broad GPU-board compatibility; up to 1.1 TB/s in one vendor example Gaming reality Bandwidth helps, but it is not the only limiter on frame rate HBM can deliver very high bandwidth in compact, tightly integrated packages, which is why it shows up in advanced multi-die designs. Consum...

Author: The Principle Lab The Real Disadvantages of HBM - Cost, Packaging Complexity, and Thermal Limits If you have been following modern accelerators, you have probably seen HBM described like the obvious answer: more bandwidth, lower power per bit, and a compact footprint. So why does it still feel like a niche tool instead of the default memory for everything? The short version is simple: the bandwidth comes bundled with real manufacturing and integration constraints that are hard to ignore. Quick summary if you are in a hurry HBM can deliver huge bandwidth by using stacked memory and a very wide interface, but that design pushes you into advanced packaging and tighter system constraints. In practice, the main blockers are (1) cost that rises with complexity, (2) packaging and assembly steps that can punish yield and rework, and (3) thermal limits that force careful temper...