Forget buying a dedicated graphics card, pretty soon you’ll be gaming without one. At least, if you’re part of the 90% of people who still game at 1080p or less. Recent advancements from both Intel and AMD mean their integrated GPUs are about to tear up the low-end graphics card market.
Why Are iGPUs So Slow in the First Place?
There are two reasons: memory and die size.
The memory part is easy to understand: faster memory equals better performance. iGPUs don’t get the benefits of fancy memory technologies like GDDR6 or HBM2, though, and instead, have to rely on sharing the system RAM with the rest of the computer. This is mostly because it’s expensive to put that memory on the chip itself, and iGPUs are usually targeted at budget gamers. This isn’t changing anytime soon, at least not from what we know now, but improving memory controllers allowing for faster RAM can improve next-gen iGPU performance.
The second reason, die size, is what’s changing in 2019. GPU dies are big—way bigger than CPUs, and big dies are bad business for silicon manufacturing. This comes down to the defect rate. A larger area has a higher chance of defects, and one defect in the die can mean the whole CPU is toast.
You can see in this (hypothetical) example below that doubling the die size results in a much lower yield because each defect lands in a much larger area. Depending on where the defects occur, they can render an entire CPU worthless. This example isn’t exaggerated for effect; depending on the CPU, the integrated graphics can take up nearly half the die.
Die space is sold to different component manufacturers at a very high premium, so it’s hard to justify investing a ton of space into a much better iGPU when that space could be used for other things like increased core counts. It’s not that the tech isn’t there; if Intel or AMD wanted to make a chip that was 90% GPU, they could, but their yields with a monolithic design would be so low that it wouldn’t even be worth it.
