Official RDNA 3 spec leak suggests AMD RX 7800 XT may not even exist

AMD launched its Radeon RX 7000 series graphics cards, based on the new RDNA 3 micro-architecture last month. While the company was pretty tight-lipped about the performance of its new 7900 series GPUs on that day, Team Red did share more details on the expected performance, though no comparisons against Nvidia's RTX 4090 or previous gen 3000 series were made.

Using the numbers provided by AMD, we estimated the expected performance of the flagship $999 RX 7900 XTX as well as the $899 RX 7900 XT. The estimated performance is pretty much in line with what one would have guessed from judging by the last gen, ie, the rasterization throughput is better than the RTX 4080 but it cannot compete in terms of ray tracing. The $1,599 RTX 4090, though, remains untouched as neither the 7900 XT nor the 7900 XTX is anywhere close.

Aside from these two, AMD is also supposedly going to launch the RX 7800 series next year. While the 7900 series is based on Navi 31, the RX 7800 series, which is a tier-below product, is expected to be based on the Navi 32 instead. And like early reports had suggested, we now know that the Navi 32 consists of 30 Work Group Processors (WGPs) or 60 Compute Units. That's because AMD's ROCmWMMA GitHub repository posted the following information recently which confirms the CU counts of the Navi 3x hardware.

60 CU RX 7800 XT or RX 7800?

While we have the overall specifications of the Navi 3x now, it is hard to say right now what the exact specifications of the RX 7800 series will be. However, if the RX 7800 XT is indeed a 60CU SKUthen, depending on how AMD prices that SKU, it will likely be seen as a failure as the 6800 XT had 12 more compute units at 72. This means the performance uplift gen-on-gen will be extremely poor if not non-existent for the 7800 XT.

Another possibility is that the full Navi 32 60 CU die actually becomes the RX 7800 non-XT. This will make much more sense as an upgrade over the RX 6800. If the latter is the case then AMD will cut the Navi 31 further down beyond 84 CUs that we have on the 7900 XT.

However, early rumors do not indicate of such any such chip existing which means AMD may not have any RX 7800 XT in the works at all. So users who have a 6800 XT now will have to move up a tier to the RX 7900 series, which is priced significantly higher than what the 6800 XT or even the 6900 XT are currently selling for.

Source: AMD (GitHub) via Kepler (Twitter)

Official RDNA 3 spec leak suggests AMD RX 7800 XT may not even exist