Nvidia's GeForce RTX 30-series are the reigning champs on our best graphics cards standings, but they might not be there for long. A Redditor has discovered the potential specifications for the Radeon RX 6000 series in Apple's macOS Big Sur 11 beta, and they look promising.
The Redditor has a good track record with leaks, but we should still exercise caution with the specifications. For starters, Apple is fond of using AMD's Radeon Pro graphics cards in its products, so the specifications may be for those specific SKUs. On the other hand, the mainstream versions will likely arrive with higher clock speeds.
To start things off, Navi 21 (Sienna Cichlid) appears to have 80 Compute Units or 5,120 Stream Processors (SPs), assuming that each CU still carries 64 SPs on RDNA 2. According to the chip detective, there were mentions of two different dies: The Navi21A silicon showed a boost clock up to 2,050 MHz, while the Navi 21B silicon surfaced with a 2,200 MHz boost clock. The power limit varies from 220W to 238W.
There is more to a graphics card than just single-precision (FP32) performance, and that value alone doesn't dictate gaming performance. Just for comparison, the GeForce RTX 3080 offers a peak single-precision performance of 29.8 TFLOPs. In comparison, the single-precision performance for Navi 21 comes out to 22.5 TFLOPs. So far, the GeForce RTX 3080 seemingly has 32.4% higher single-precision performance than Navi 21. However, Navi 21 does pull a win over the GeForce RTX 3070, which is good for 20.4 TFLOPs.
AMD's RDNA 1 architecture delivered a 50% performance uplift over the prior Graphics Core Next (GCN) architecture that survived for so long and still going strong. The chipmaker has promised that we would see the same level of advancement with RDNA 2.
| Silicon | Codename | Compute Units | Stream Processors | Clock Speed (MHz) | Single-Precision Performance (TFLOPs) | Power Limit (W) |
|---|---|---|---|---|---|---|
| Navi 31 | ? | 80 | 5,120 | ? | ? | ? |
| Navi 21 | Sienna Cichlid | 80 | 5,120 | 2,050 - 2,200 | 21 - 22.5 | 200 - 238 |
| Navi 22 | Navy Flounder | 40 | 2,560 | 2,500 | 12.8 | 170 |
| Navi 10 (Radeon RX 5700 XT) | ? | 40 | 2,560 | 1,905 | 9.8 | 225 |
| Navi 23 | Dimgrey Cavefish | 32 | 2,408 | ? | ? | ? |
| Navi 14 ( Radeon RX 5500 XT) | ? | 22 | 1,408 | 1,845 | 5.2 | 130 |
Navi 22 (Navy Flounder) might arrive with 40 CUs, amounting to a total of 2,560 SPs. For the observant, that's the same number of CUs as found on Navi 10. It's safe to assume that Navi 22 is the direct successor to Navi 10. However, Navi 22 looks more impressive with its boost clock at 2,500 MHz within a 170W power limit.
The Radeon RX 5700 XT, based on Navi 10, comes equipped with 2,560 SPs with a boost clock of 1,905 MHz. The graphics card has a maximum single-precision performance of 9.8 TFLOPs. Navi 22 delivers 12.8 TFLOPs of FP32 shader performance, so we're looking at a 30.6% improvement. That's not to mention within a lower power requirement, remembering that the Radeon RX 5700 XT is rated for 225W.
Navi 23 (Dimgrey Cavefish) would be the entry-level RDNA 2 silicon. The Navi 23 die may end up with 32 CUs (2,048 SPs). Unfortunately, the clock speeds and power limits for Navi 23 weren't hidden inside Apple's firmware.
Astoundingly, Apple already has an RDNA 3 graphics card in its macOS Big Sur 11 beta code. There was mention of a Navi 31 silicon, which we expect to see in the Radeon RX 7000 series. According to the Redditor's findings, Navi 31 has the same number of CUs as Navi 21. At the moment, it's unknown if Navi 31 will be a proper replacement or just a refresh for Navi 21, though.
AMD will announce its Radeon RX 6000 series on October 28. Nvidia's GeForce RTX 30-series has had a rocky launch. The graphics cards not only sparked a war between consumers and scalpers, but have also been plagued by serious stability issues, too. Let's hope AMD delights us with a smooth launch and ample availability.
