In a new rumor from Greymon55, it looks like AMD’s RDNA 3 based Navi 33 GPU which will power the next-gen Radeon RX 7000 series graphics cards will feature fewer cores than expected at first.
AMD Radeon RX 7000 ‘RDNA 3’ Navi 33 GPU Rumored To Feature 4096 Cores But Performance Faster Than Navi 21
Previously, Greymon55 had stated up to 5120 cores or 20 WGP’s on the RDNA 3 based Navi 33 GPU but his latest information suggests a lower WGP and Core count. But that doesn’t mean the overall performance has changed. Despite the lower number, the Navi 33 GPU will be offering faster GPU performance than the Navi 21 GPU which is currently AMD’s flagship RDNA 2 chip for the high-end segment.
AMD RDNA 3 Navi 33 GPUs For Radeon RX 7700 Series
The AMD Navi 33 GPU will start the monolithic segment within the RDNA 3 family. The GPU will feature a single die. The die is very similar to the flagship Navi 21 GPU and is expected to utilize a 6nm process node for fabrication.
A preliminary block diagram of AMD’s next-gen RDNA 3 based Navi 33 GPU that will power the flagship Radeon RX 7600 XT graphics card. (Image Credits: Olrak)
The Navi 33 GCD is expected to feature 2 Shader Engines and each Shader Engine has 2 Shader Arrays (2 per SE / 4 in total). Each Shader Array was previously expected to be composed of 5 WGPs (10 per SE / 20 total) and each WGP features 8 SIMD32 units with 32 ALUs (40 SIMD32 per SA / 80 per SE / 160 total). These SIMD32 units combine to make up 5120 cores which is the same core count as the RX 6900 XT (Navi 21 XTX GPU).
However, based on the new numbers, the RDNA 3 Navi 33 GPU will feature a total of 16 WGPs or 4096 cores. Now we don’t know if this is the particular configuration of the chip itself that’s been updated or the new Radeon RX 7000 cards will feature a cut-down configuration of the Navi 33 chips with 1 WGP disabled in each Shader Array.
n33 was designed to be better than the 6900xt, and even if it didn’t meet its design goal, its performance was still around 6900xt.
— Greymon55 (@greymon55) September 22, 2021
That’s true. N33=N23+GFX11.
— kopite7kimi (@kopite7kimi) September 29, 2021
To make things interesting, Kopite7kimi states that Navi 33 is Navi 23’s replacement on the GFX11 architecture but we know that Navi 23 only features 2048 cores, half the amount that’s allegedly featured on Navi 33. The Navi 23 GPU has been featured on the Radeon RX 6600 series cards so one can assume that Navi 33 will power AMD’s RX 7600 series lineup unless AMD wants to move their lineup one tier up with Navi 31 powering RX 7900 series, Navi 32 powering RX 7800 series & Navi 33 powering RX 7700 series. The RX 7600 lineup and below would end up being based on the refreshed 6nm RDNA 2 GPUs as reported here.
AMD RDNA 3 Navi 3X GPU Configurations (Preliminary)
GPU Name | Navi 21 | Navi 33 | Navi 32 | Navi 31 |
---|---|---|---|---|
GPU Process | 7nm | 6nm | 5nm/6nm | 5nm/6nm |
GPU Package | Monolithic | Monolithic | MCM | MCM |
Shader Engines | 4 | 2 | 4 (2 per GCD) | 6 (3 per GCD) |
GPU WGPs | 40 | 20 | 40 (20 per GCD) | 60 (30 per GCD) |
SPs Per WGP | 128 | 256 | 256 | 256 |
Compute Units (Per Die) | 80 | 40 | 80 160 (Total) |
120 240 (Total) |
Cores (Per Die) | 5120 | 5120 | 5120 | 7689 |
Cores (Total) | 5120 | 5120 | 10240 | 15360 |
Memory Bus | 256-bit | 128-bit | 192-bit | 256-bit |
Memory Type | GDDR6 | GDDR6 | GDDR6 | GDDR6 |
Infinity Cache | 128 MB | 256 MB | 384 MB | 512 MB |
Flagship SKU | Radeon RX 6900 XTX | Radeon RX 7700 XT? | Radeon RX 7800 XT? | Radeon RX 7900 XT? |
TBP | 330W | ~200W | ~300W | ~400W |
Launch | Q4 2020 | Q4 2021? | Q4 2021? | Q4 2021? |
The Navi 33 (RDNA 3) is expected to carry 256 MB of Infinity Cache. Each GPU should also feature 2 memory connect links (32-bit). That’s a total of 4 32-bit memory controllers for a 128-bit bus interface. This would bring the performance of the AMD Radeon RX 7600 series above the RX 6800 and RX 6900 series at a TDP of around 200W. The Navi 33 GPU is expected to be taped out soon & launch is expected around October 2022.
AMD RDNA Generational GPU Lineup
Radeon Lineup | Radeon RX 5000 | Radeon RX 6000 | Radeon RX 7000 | Radeon RX 8000 |
---|---|---|---|---|
GPU Architecture | RDNA 1 | RDNA 2 | RDNA 3 / RDNA 2 | RDNA 4 |
Process Node | 7nm | 7nm | 5nm/6nm? | 5nm/3nm? |
GPU Family | Navi 1X | Navi 2X | Navi 3X | Navi 4X |
Flagship GPU | N/A | Navi 21 (5120 SPs) | Navi 31 (15360 SPs) | Navi 41 |
High-End GPU | Navi 10 (2560 SPs) | Navi 22 (2560 SPs) | Navi 32 (10240 SPs) | Navi 42 |
Mid-Tier GPU | Navi 12 (2560 SPs) | Navi 23 (2048 SPs) | Navi 33 (5120 SPs) | Navi 43 |
Entry-Tier GPU | Navi 14 (1536 SPs) | Navi 24 (1024 SPs) | Navi 34 (2560 SPs) | Navi 44 |