Continuing with AMD's tendency for fishy codenames, the chipmaker (via @Komachi Ensaka (opens in new tab)) has added support for a Dimgrey Cavefish graphics card to Mesa 20.3-devel (opens in new tab). Much like Sienna Cichlid (opens in new tab) and Navy Flounder (opens in new tab), Dimgrey Cavefish is presumed to be a RDNA 2 graphics cards that'll surely unsettle the gaming graphics card hierachy (opens in new tab) as we know it.
AMD has already committed to lift the curtains for the Radeon RX 6000 series (opens in new tab), which have been popularly baptized as Big Navi (opens in new tab), on October 28. Therefore, it's not too surprising that the chipmaker's trio of next-generation graphics cards are doing their rounds in the wild. We don't have any factual information on AMD's RDNA 2 product stack so it's wise to treat the specifications that are going around the hardware world with a truckload of salt.
Assuming that each Compute Unit (CU) in AMD's RDNA 2 architecture still equates to 64 Stream Processors (SPs), we can piece together some of the rumored specifications for AMD's Radeon RX 6000-series graphics cards.
AMD Radeon RX 6000 Specifications*
|Graphics Card||Codename||Silicon||Compute Units||Stream Processors|
|Radeon RX 6900||Sienna Cichlid||Navi 21||80||5,120|
|Radeon RX 6800, RX 6700||Navy Flounder||Navi 22||40||2,560|
|Radeon RX 6600, RX 6500||Dimgrey Cavefish||Navi 23||?||?|
*Specifications are unconfirmed.
At the current time, Sienna Cichlid is associated with the Navi 21 silicon. If the current prediction is accurate (opens in new tab), Sienna Cichlid could end up with 80 CUs or 5,120 SPs. This would mean that Sienna Cichlid is likely to be the flagship, in which event, would be the Radeon RX 6900.
If Sienna Cichlid corresponds to Navi 21, then Navy Flounder should be Navi 22. Thus far, the silicon is rumored to bring 40 CUs, which amounts to 2,560 SPs. There is a good possibility that Navy Flounder could be the direct replacement for the current Radeon RX 5700 (XT) (opens in new tab). If that's the case, Navy Flounder must be the Radeon RX 6700 although we can't discard the probability of it being a Radeon RX 6800.
The Dimgrey Cavefish is the latest RDNA 2 codename to pop up. Common wisdom tells us that Dimgrey Cavefish must be Navi 23, the last piece to the puzzle. The only logical assumption is that Navi 23 will be featured in either the Radeon RX 6600 or RX 6500, depending on AMD's intentions.
It's uncertain which graphics card AMD will announce on October 28. The chipmaker vaguely used the Radeon RX 6000 moniker. If we look back at RDNA 1, AMD started with the Radeon RX 5700 (XT) and eventually went down the pile. Being optimistic, we would love for AMD to reveal Big Navi because the current graphics card market needs some competition in the higher tiers. Nvidia's recent GeForce RTX 3080 (opens in new tab) has proven to be a tough cookie, and Big Navi will likely be the most worthy competitor.