RX 7900 XTX Features The Bug Infested A0 Silicon Revision

It is no surprise that AMD’s RDNA3 GPUs perform, interestingly to say the least. These GPUs were tipped to match the RTX 4090, however, the actual performance says otherwise. Many enthusiasts state that Navi31, the GPU behind the 7900 XTX is prone to some serious hardware bugs.

Navi31, What Went Wrong

AMD claimed that the 7900 XTX was around 60% faster than the RX 6950 XT but the results are in front of us. One might say that the pricing makes it on par with the RTX 4080. This means that it should outperform the RTX 4080, which it does but at higher power consumption. 

It was initially thought that the RX 7900 XTX uses the C8 silicon revision. However, on further investigation davidbepo found out that this GPU uses the A0 revision. Reportedly, Navi31 was delayed for almost one year but AMD failed to make any significant improvements.

It is also speculated that the numbers AMD showed at the RDNA3 reveal were estimated. This means that AMD hoped to fix these hardware bugs before RDNA3 went live and sadly they couldn’t manage to complete this tedious task. This is exactly why these GPUs were launched more than a month after the reveal.

Furthermore, Kepler claims that the A0 revision has a non-working shader prefetch. In RDNA2, the performance penalty due to this revision was 5%. As the architecture itself has changed quite a bit with RDNA3, the performance loss can be higher or lower. Adding insult to injury, Navi33 and Phoenix suffer from the same fate as we reported before. Now only time will tell if AMD can fix Navi33 before NVIDIA launches its budget GPUs.

Very early leaks suggested that Navi3X could go as high as 4GHz. At launch, it became clear that Navi31 was expected to at least pass the 3GHz mark but is unable to do so. In various games, the clocks can vary between 2.4GHz and 2.9GHz. The difference went as high as 1.4GHz which is no joke. Sadly, this shows that RDNA3 was on paper much more capable but could not live up to expectations.

RDNA3+

Leaks suggest that AMD will launch the RDNA3 refresh codenamed RDNA3+ next year. As of now, only Navi31 and Navi33 will be revised. Navi32 surprisingly does not suffer from such issues. Also, these problems cannot be fixed in mere days. Kepler claims that it may take AMD months if they decide to pay heed to these issues. RDNA3+ on the other hand will feature some architectural changes. 

All in all, it is disappointing how AMD had the perfect product but could not make the most of it. Navi32 will be the real test for RDNA3 as it is not vulnerable to such problems. 

SKU Chip CU (128 Shading Units/ 1 CU) CU (64 Shading Units/ 1 CU) FP32 Max Clock Cache Memory Bus VRAM Memory Spec Speed (Gbps)
RX 7950XT3D Navi31 96 192 12288 2.5GHz? 192MB? 384-bit 24GB GDDR6 20
RX 7900 XTX Navi31 96 192 12288 2.5GHz 96MB 384-bit 24GB GDDR6 20
RX 7900XT Navi31 84 168 10752 2.4GHz 80MB 320-bit 20GB GDDR6 20
RX 7800XT Navi32 60 120 7680 64MB 256-bit 16GB GDDR6 18
RX 7800 Navi32 56 112 7168 48MB? 256-bit 16GB GDDR6 18
RX 7700XT Navi32 48 96 6144 48MB? 192-bit 12GB GDDR6 18
RX 7700 Navi32? 40 80 5120 40MB? 160-bit? 10GB? GDDR6 18
RX 7600XT Navi33 32 64 4096 32MB 128-bit 8GB GDDR6 18
RX 7600 Navi33 28 56 3584 32MB? 128-bit 8GB GDDR6 18

 

Source: davidbepo , Kepler

ABOUT THE AUTHOR

Abdullah Faisal


With a love for computers since the age of five, Abdullah has always sought to delve into the depths of information, and uses it as his guiding light. He believes success is of utmost importance as history is written by the victor.