An update to AMD's ROCm general-purpose GPU software, the upcoming Navi 32 (opens in new tab) and Navi 33 (opens in new tab) graphics chips that are likely to be released in the RDNA 3 series (aka Radeon RX-7000 series) The specs have reportedly been revealed. Where these new chips will be positioned in AMD's new Radeon RX 7000 series (opens in new tab) is a really big question.

Are these chips the basis for the upcoming Radeon RX 7800 and 7700 GPUs? Deep in the ROCm file called "performance.hpp" there are references to both Navi 32 and Navi. However, the really important numbers in this file are 60 and 32, which are talking about CUs (compute units). To understand what these numbers mean, the Navi 31 chip in the AMD Radeon RX 7900 XT and XTX graphics cards runs at 96 CUs.

Assuming the same CU sub-structure for all three GPUs with 64 stream processors in each CU, Navi 31 has 6,144 stream processors, Navi 32 has 3,840 stream processors and Navi 33 has 2,048 processors. For further background, the Navi 21 GPU in the Radeon RX 6900 XT (open in new tab) has 80 CUs and 5,120 processors, while the Navi 22 in the 6700 XT has 40 CUs and 2,560 processors.

A slight complication is that the stream processors in the new RDNA 3 chip are double-pumped and can handle twice as many FP32 operations as the RDNA 2 stream processor, but not twice as many integer operations. This is a troubling complication, as the Navi 31 sometimes acts as if it has 12,288 processors, but this is not always the case.

The same applies to Navi 32 and Navi 33. Thus, Navi 32 can be said to have 3,840 processors, which is not that impressive considering that the previous generation RDNA 2 architecture was scaled up to 5,120, or we could call it 7,680 processors.

So where do the Navi 32 and Navi 33 fit in AMD's new RX 7000 series lineup? In the previous RDNA 2 generation, AMD actually based the Radeon RX 6800 and 6800 XT (open in new tab) on the larger Navi 21. Unfortunately, just as Nvidia relegated the GeForce RTX 4080 to the smaller AD104 chip instead of basing it on the larger AD102 beast, it seems likely that AMD will do the same this time.

In other words, the Radeon RX 7800 and 7800 XT will probably be based on the Navi 32 this time around. Thus, at best, the 7800 XT will offer 62.5% of the physical hardware of the 7900 XTX. By comparison, the old 6800 XT is 90% of the 6900 XT; like Nvidia, this generation of AMD boards is likely to have a larger gap between the top-class cards and the next-ranked cards.

As for Navi 33, its chip will be the basis for the Radeon RX 7700 and 7700 XT. Notably, Navi 33 is expected to run with 128-bit memory, a step down from the Radeon RX 6700 XT's 192-bit bus. (Open in new tab) Furthermore, in the smaller of the two measures of stream processor count, the 7700 XT will step down to just 2048 processors from the 6700 XT's 2560 processors.

While this may not sound promising on its own, the wild card that changes everything is the clock speed; AMD has publicly stated that RDNA 3 is designed for clock speeds above 3 GHz. For reasons that are not yet clear, AMD has not been able to come close to those numbers with its first RDNA 3 GPU, the Navi 31

. [However, there have been rumors of clock speeds above 3.3 GHz on various RDNA 3 GPUs for some time now. For reference, the 6700 XT has a maximum boost clock speed of just under 2.6 GHz. All of this suggests that the upcoming 7800 XT and 7700 XT graphics cards could offer a very healthy performance boost over AMD's existing mid- and upper-mid-tier GPUs if they can achieve frequencies above 3 GHz on smaller chips.

Fingers crossed!