For months now, we’ve been hearing rumors that AMD gave up on its best graphics card from the upcoming RDNA 4 lineup, and instead opted to target the midrange segment. However, that doesn’t mean that such a GPU was never in the works. Data mining revealed that the card may indeed have been planned, and if it was ever released, it would’ve given Nvidia’s RTX 4090 a run for its money.
The top GPU in question, commonly referred to as Navi 4C or Navi 4X, was spotted in some patch information for AMD’s GFX12 lineup — which appears to be a code name for RDNA 4. The data was then posted by Kepler_L2, a well-known hardware leaker, on Anandtech forums. What at first glance seems to be many lines of code actually reveals the specs of the reportedly canceled graphics card.
These are not the full specs that we’re getting, of course, but what we’re seeing here is perhaps the most important specification — the number of shader engines, ranging from zero to eight, for a total of nine. This implies a very high-end design for the RDNA 4 flagship and would mark a significant increase over the RX 7900 XTX, which sports six shader engines. In the same discussion thread, another user reported that the Navi 4X GPU was meant to have over 200 compute units (CUs). That’s twice the number of the RX 7900 XTX, which comes with 96 CUs.
The graphics card was also said to feature a major architectural change, sporting three graphics compute dies (GCDs), each with three shader engines. This is the multi-chiplet design that leakers first mentioned as a possibility for RDNA 3, then RDNA 4, and now, RDNA 5. Regardless of architecture, such an increase in CUs would make for a competitive GPU.
For comparison, if this rumored RX 8900 XTX would have been twice as fast as the RX 7900 XTX, it could outperform Nvidia’s RTX 4090 in raw rasterization. There would still be DLSS 3 to give Nvidia a boost, but that wouldn’t have made it less of a major win for AMD.
However, by the time this GPU would have comeout, Nvidia’s RTX 5090 would have been right around the corner, most likely ready to claim the crown yet again, along with the rest of the RTX 50-series. That could be why AMD is reportedly sticking to less extreme GPUs in the upcoming generation.
These few lines of code are perhaps the most tangible leak we’ve had about this GPU so far, but the truth is that we don’t know anything for a fact just yet. AMD is yet to confirm anything one way or the other. But most leakers agree — this GPU, however great it might have been, will not see the light of day in this generation of graphics cards.
