Radeon Surprise: AMD Demos a Chiplet-Powered RDNA 3 RX 7000 Graphics Card

AMD’s next generation of graphics cards is right around the corner, and they are promising to be revolutionary, regardless of whether they turn out to be performance leaders. That’s because the upcoming AMD Radeon RX 7000 series of graphics cards will be the first from AMD based on a chiplet design, according to comments made by Chair and CEO Dr. Lisa Su at the company’s Ryzen 7000 launch event today. She also reiterated, in passing, AMD’s launch date of later this year for the first of these next-gen graphics cards, which will be based on the coming RDNA 3 architecture and 5nm process technology.

If you’ve been following AMD’s Ryzen processors, you may realize just how significant the chiplet aspect of this tease is, and you should also know it’s something that could help to cut down the cost of the GPUs. Before we get down into the hints Dr. Su dropped, let’s get into a bit of context.

First, Some Background: Chiplets vs. Monoliths

Chiplet designs are not exactly new, but recently we have been seeing AMD and now Intel take them to new heights. Essentially, a chiplet design consists of two or more independent silicon chips that have been tightly coupled into a single package. As an illustration, see this image from Intel, which illustrates a conventional single-chip silicon package on the left and a silicon package with four chiplets in the center and on the right.

(Credit: Intel)

The use of chiplets is significant, as it can ease the development of different products and help to reduce production costs. When you create processors out of silicon, a small defect anywhere on the chip can cause the entire chip to be nonfunctional. This makes large chips that have larger areas more prone to such killer defects, and they are more costly to manufacture due to the added time and resources used in their production. In contrast, smaller chips can be cheaper to produce for the opposite reasons.

Let’s say, for example, you have one chip with an area of 20mm2. Directly beside it, you create four chips, each with an area of 5mm2 and an accumulative area of 20mm2. The large chip is then exactly the same size as the four smaller chips, and it may have taken roughly the same amount of resources to produce. If so much as a speck of dust lands anywhere on that large 20mm2 die during manufacture, it could be completely ruined. Conversely, if that speck of dust landed on one of those other four chips, then only that one 5mm2 die would be done for, which means you wasted less resources overall.

Chiplets in…GPUs?

This is a key benefit to using smaller chips, but it’s not the only benefit. Chiplets also allow for far greater flexibility in creating products. Using a traditional chip-design approach, AMD would need to design and manufacture multiple iterations of a graphics chip to feed the full product line. In the Ryzen RX 6000 series, for example, AMD created four chips: Navi 21, Navi 22, Navi 23, and Navi 24.

The AMD Radeon RX 6800 XT
(Credit: Zlata Ivleva)

Select GPUs will have the full chip enabled, whereas other GPUs will have a partially disabled chip to create slightly lower-end products. The Radeon RX 6900 XT, for example, has 5,120 stream processors, whereas the Radeon RX 6800 XT has 4,608 stream processors even though both contain a Navi 21 chip. This again, however, wastes some amount of resources.

Using multiple smaller chips can be more economical in this regard. If, for example, AMD creates RDNA 3 chips with, say, 1,024 streaming processors each, the company could make use of five of these chips together to construct a graphics card with a similar number of streaming processors as the Radeon RX 6900 XT. At the same time, it could create a budget-friendly graphics card by using just one of these chiplets. This not only wastes fewer resources, but it also streamlines production, as you need to create just one chip and package it in various configurations, instead of crafting multiple chips.

Nothing in life is free, though, and there is a performance penalty associated with using chiplets. The individual parts of the chip are able to communicate with each other faster in a single-chip design than in a chiplet design. It therefore becomes a balancing act of weighing the pros and cons of each solution. Large, monolithic chips have been the favorite in both the CPU and GPU world for decades now.

Chiplets didn’t become truly widely used until AMD launched its first generation of Ryzen processors, and given how well that has gone, it seems clear that AMD thinks it can benefit its graphics-card business, too.

What We Know Now About RDNA 3

In short: Not a whole lot. We will have to wait and see how this launch will play out. At this time, we have precious few details about RDNA 3 or the upcoming Radeon RX 7000 series of graphics cards apart from the info-breadcrumbs dropped at today’s event, which reinforce statements made at an AMD investor conference this past summer. That said, today’s announcement by Dr. Su, in passing, suggests a new generation of Radeon isn’t far away. Indeed, cards are up and running.

At the end of its Ryzen 7000 presentation today in Austin, Texas, Dr. Su showed off a rendered image of an RDNA 3-based GPU, followed by a demo of the card in action. You can see a replay of the announcement stream here, and for the good stuff around RDNA 3, cycle forward to around the 31-minute mark…

In the demo, the card was running NeoWiz’s breakout game Lies of P(Opens in a new window) in 4K and Ultra settings, at what appeared to be a buttery-smooth level of performance. The processor it was paired with was the newly announced, not-yet-released Ryzen 9 7950X 16-core flagship. We were also told (in line with original claims from the investor conference) that the Radeon RX 7000 series will have cards with 50% more performance per watt than their predecessors, which is quite impressive…assuming it pans out.

(Credit: AMD)

Listen carefully, and Dr. Su mentions in passing around 32 minutes, “I can’t wait to tell you more about it when we launch later this year.” So: no fixed date quite yet, but we shouldn’t expect Ryzen 7000 to be AMD’s last big word in the consumer PC-component market this year. Next-gen Radeon appears to still be on track for 2022. Stay tuned.