As we get closer and closer to the official reveal of AMD’s next generation of Radeon graphics cards, rumors and leaks start to come out hot and fast, just like what happened before Nvidia’s RTX 30 series announcement. This time however, the leak was due to a recent Linux update, and seems to have spilled the specs on 2 of AMD’s upcoming GPUs.

Sienna Cichlid and Navy Flounder are codenames for AMD’s next-gen graphics cards, referring to the famed Big Navi (or Navi 21) and the Navi 22/23 respectively. We’re unsure whether the Navy Flounder is the Navi 22 or Navi 23 GPU, but we do know that Sienna Cichlid refers to the flagship Big Navi card at least.

Thanks to a nifty Reddit user, known as u/stblr, who went searching in the ROCm (Radeon Open Computer) code, some interesting specs have been seen related to the 2 aforementioned GPUs. You can check out the alleged specs below (the data is a bit hard to decipher if you don’t know what’s going, don’t worry though, we explain the most important stuff underneath):

Parameter Navy Flounder (Navi 22/Navi 23) Sienna Chichlid (Big Navi/Navi 21)
gc_num_se 2 4
gc_num_cu_per_sh 10 10
gc_num_sh_per_se 2 2
gc_num_rb_per_se 4 4
gc_num_tccs 12 16
gc_num_gprs 1024 1024
gc_num_max_gs_thds 32 32
gc_gs_table_depth 32 32
gc_gsprim_buff_depth 1792 1792
gc_double_offchip_lds_buffer 1024 1024
gc_wave_size 32 32
gc_max_waves_per_simd 16 16
gc_lds_size 64 64
num_sc_per_sh 1 1
num_packer_per_sc 4 4

Most interestingly, by multiplying the top 3 numbers together for each GPU you can work out the total amount of Compute Units per card. So for the Navy Flounder that’s 40 CUs, whereas the Sienna Cichlid has 80 CUs. The document also seems to suggest that the Sienna Cichlid will come with a 256-bit bus width, and the Navy Flounder will have a bus width of 192-bit.

Rumors suggest that performance for the flagship Sienna Cichlid GPU (Big Navi) will come close to the performance of an RTX 3080, whilst the Navy Flounder is reportedly just an updated RX 5700 XT but now with all the fancy tech required for ray tracing.

Of course, whilst this is from official Linux kernel code, this information should be taken with a grain of salt, as it is still speculation based on data that has been unconfirmed and is subject to change. Nevertheless, it is quite exciting, but we’ll have to wait for official confirmation on October 28th when AMD officially reveals the next-gen Radeon RX 6000 GPUs.

What do you think? Are you excited for AMD’s next-gen cards? What about the Big Navi? And how much do you think they will cost? Let us know!