The Radeon open compute (ROCm) firmware was recently updated and has revealed some interesting information nuggets. Redditor stblr spotted the changes to the firmware file which according to their analysis reveals previously unknown info about an AMD GPU codenamed Navy Flounder.
So, what exactly is revealed by this ROCm v3.8 Linux firmware file? It contains the reference and values table as reproduced below:
Redditor stblr explains that interested parties can derive the number of Compute Units (CUs) in the particular GPU by multiplying the top three values together. Another key value indicated by these tables is the memory bus width indicated by the gc_num_tccs value (but there are sometimes exceptions to this value relationship).
Weighing up the above we get the following data:
Sienna Cichlid (Big Navi or Navi 21) |
Navy Flounder (Navi 22 or 23) |
80 compute units |
40 compute units |
256-bit GDDR6 memory |
192-bit GDDR6 memory |
If each CU has 64 stream processors, as was the case with RDNA 1 GPUs, then Navy Flounder will be pretty similar in basic configuration to the Radeon RX 5700 XT but with the new architecture and of course it will be positioned at a new competitive level against the latest announced and expected Nvidia Ampere GPUs.
For next-gen console reference, the Xbox Series X SoC features 52 RDNA 2 CUs at 1.83GHz, meanwhile the PlayStation 5 SoC features 36 RDNA 2 CUs at 2.23GHz.
Source: Reddit via Tom's Hardware.